Administering a multitenant container database (CDB) includes tasks such as accessing a container, modifying a CDB, executing DDL statements, and running Oracle-supplied SQL scripts.
Administering a CDB is similar to administering a non-CDB, with some differences.
Most differences occur because some administrative tasks apply to the entire CDB, whereas others apply to specific containers.
Current Container
The data dictionary in each container in a CDB is separate, and the current container is the container whose data dictionary is used for name resolution and for privilege authorization.
The current container can be the CDB root, an application root, a PDB, or an application PDB. Each session has exactly one current container at any point in time. However, a session can switch from one container to another.
Each container has a unique ID and name in a CDB. You can use the CON_ID
and CON_NAME
parameters in the USERENV
namespace to determine the current container ID and name with the SYS_CONTEXT
function. For example, the following query returns the current container name:
SELECT SYS_CONTEXT ('USERENV', 'CON_NAME') FROM DUAL;
You can access a container in various ways. For example, you can use the SQL*Plus CONNECT
command, and you can use an ALTER SESSION SET CONTAINER
statement to switch the container of the current session.
The following rules apply to the current container in a CDB:
- The current container can be
CDB$ROOT
(CDB root) only for common users. - The current container can be a specific PDB for common users and local users.
- The current container can be an application root only for common users or for application common users created in the application root.
- The current container can be a specific application PDB for common users, application common users, and local users.
- The current container must be the CDB root or an application root when a SQL statement includes
CONTAINER = ALL
.
You can include the CONTAINER
clause in several SQL statements, such as the CREATE USER
, ALTER USER
, CREATE ROLE
, GRANT
, REVOKE
, and ALTER SYSTEM
statements. Note the following rules about CONTAINER = ALL
:
- When a SQL statement includes
CONTAINER = ALL
and the current container is the CDB root, the SQL statement affects all containers in the CDB, including all PDBs, application roots, and application PDBs.- When a SQL statement includes
CONTAINER = ALL
and the current container is an application root, the SQL statement affects all containers in the application container, including the application root and all the application PDBs that belong to the application root. The SQL statement does not affect the CDB root or any PDBs or application PDBs that do not belong to the current application root.
- Only a common user or application common user with the commonly granted
SET CONTAINER
privilege can run a SQL statement that includesCONTAINER = ALL
.
- When a SQL statement includes
Administrative Tasks in a CDB
Common users perform administrative tasks for a CDB.
A common user has a single identity and can log in to the CDB root, any application root, PDB, or application PDB in which it has privileges. Some tasks, such as starting up a CDB instance, can be performed only by a common user.
Other administrative tasks are the same for a CDB and a non-CDB. The following table describes some of these tasks and provides pointers to the relevant documentation.
Administrative Tasks Common to CDBs and Non-CDBs
Task | Description |
Starting up a CDB instance | To start a CDB instance, the current user must be a common user whose current container is the CDB root. When you open a CDB, the CDB root is opened, but its other containers are mounted. Use the ALTER PLUGGABLE DATABASE statement to modify the open mode of one or more containers. |
Managing processes | A CDB has one set of background processes shared by the CDB root and all containers. |
Managing memory | A CDB has a single system global area (SGA) and a single aggregate program global area (PGA). The memory required by a CDB is the sum of the memory requirements for all containers that will be part of the CDB. |
Managing security | You can create and drop common users, application common users, and local users in a CDB. You can also grant privileges to and revoke privileges from these users. You can also manage the CONTAINER_DATA attributes of common users and application common users. In addition, grant the following roles to the appropriate users: Grant the CDB_DBA role to CDB administrators.Grant the PDB_DBA role to application container administrators and PDB administrators. |
Monitoring errors and alerts | A CDB has one alert log for the entire CDB. The name of an application container, PDB, or application PDB is included in records in trace files, when appropriate. |
Managing diagnostic data | In a CDB, you can use the Oracle Database fault diagnosability infrastructure and the Automatic Diagnostic Repository (ADR). |
Managing control files | A CDB has one control file. |
Managing the online redo log and the archived redo log files | A CDB has one online redo log and one set of archived redo log files. |
Managing tablespaces | You can create, modify, and drop tablespaces and temporary tablespaces for the CDB root and for individual containers. You can also specify a default tablespace, default tablespace type, and a default temporary tablespace for the CDB root. The CDB root has its own set of Oracle-supplied tablespaces, such as the SYSTEM tablespace, and other containers have their own set of Oracle-supplied tablespaces. |
Managing data files and temp files | The CDB root has its own data files, and other containers have their own data files. In a CDB, you can manage data files and temp files in basically the same way you would manage them for a non-CDB. However, the following exceptions apply to CDBs: You can limit the amount of storage used by the data files for a container by using the STORAGE clause in a CREATE PLUGGABLE DATABASE or ALTER PLUGGABLE DATABASE statement.There is a default temporary tablespace for the CDB root and for individual containers. |
Managing undo | A CDB can run in local undo mode or shared undo mode. Local undo mode means that every container in the CDB uses local undo. Shared undo mode means that there is one active undo tablespace for a single-instance CDB, or for an Oracle RAC CDB, there is one active undo tablespace for each instance. In a CDB, the UNDO_MANAGEMENT initialization parameter must be set to AUTO , and an undo tablespace is required to manage the undo data. |
Moving data between containers | You can move data between containers using the same methods that you would use to move data between non-CDBs. For example, you can transport the data or use Data Pump export/import to move the data. |
Using Oracle Managed Files | Using Oracle Managed files can simplify administration for both a CDB and a non-CDB. |
Using Transparent Data Encryption | Transparent Data Encryption is a feature that enables encryption of individual table columns before storing them in the data file, or enables encryption of entire tablespaces. In a CDB, each container has its own master key for Transparent Data Encryption, and, where applicable, the ADMINISTER KEY MANAGEMENT SQL statement enables key management at the CDB level and for individual containers. |
Using a standby database | Oracle Data Guard can configure a physical standby or a logical standby of a CDB. Data Guard operates on the entire CDB, not on individual containers in a CDB. |
Using Oracle Database Vault | Oracle Database Vault common realms can be scoped to an application root on common objects. Database Vault common command rules can be scoped to either the CDB or an application root. Local realms and command rules can be locally scoped to individual PDBs or application PDBs. When Oracle Database Vault security objects are in the CDB root or an application root, enforcement of the security objects only applies to the containers that have Oracle Database Vault enabled. |
Dropping a database | When you drop a CDB, all containers in the CDB are dropped along with their data. These containers include the CDB root and PDB seed and all application containers, application seeds, PDBs, and application PDBs. You can also drop individual application containers, application seeds, PDBs, and application PDBs with the DROP PLUGGABLE DATABASE statement. |
Using Manageability Features in a CDB
For each of Oracle Database’s manageability features in a CDB, it is important to understand the data location and the data visibility.
When feature data resides in the CDB root, the data is not included when a PDB is unplugged. When the data resides in a PDB, however, the data remains both when the PDB is unplugged and when it is plugged in.
Generally, in a CDB, a common user can view data for the CDB root and for multiple PDBs when the common user’s current container is the CDB root. A common user can view this data by querying container data objects. The specific data that is visible varies for the manageability features. A user whose current container is a PDB can view data for that PDB only.
The following table describes how the manageability features work in a CDB.
Manageability Features in a CDB
Manageability Feature | Data Location | Data Visibility |
Active Session History (ASH) ASH collects information about active database sessions. You can use this information to analyze and identify performance issues. | Most of the ASH data is stored in memory. A small percentage of the ASH data samples are stored in the CDB root. ASH data related to a PDB is not included if the PDB is unplugged. | A common user whose current container is the CDB root can view ASH data for the CDB root and for PDBs. A user whose current container is a PDB can view ASH data for the PDB only. |
Alerts An alert is a notification of a possible problem. | Threshold settings that pertain to a PDB are stored in the PDB. Alerts posted when thresholds are violated are enqueued into the alert queue in the CDB root. Threshold settings that pertain to a PDB are included if the PDB is unplugged. Alerts related to a PDB are not included if the PDB is unplugged. | A common user whose current container is the CDB root can view alerts for the CDB root and for PDBs. A user whose current container is a PDB can view alert thresholds and alerts for the PDB only. |
Automated Database Maintenance Tasks Automated database maintenance tasks are tasks that are started automatically at regular intervals to perform maintenance operations on the database. Automated tasks include automatic optimizer statistics collection, Automatic Segment Advisor tasks, and Automatic SQL Tuning Advisor tasks. The ENABLE_AUTOMATIC_MAINTENANCE_PDB initialization parameter can enable or disable the running of automated maintenance tasks for all the PDBs in a CDB or for individual PDBs in a CDB. The AUTOTASK_MAX_ACTIVE_PDBS initialization parameter limits the number of PDBs that can schedule automated maintenance tasks at the same time (during a maintenance window). | A user can schedule maintenance windows and enable or disable maintenance tasks for the current container only. If the current container is the CDB root, then the changes only apply to the CDB root. If the current container is a PDB, then the changes only apply to the PDB. Data related to a PDB is stored in the PDB for automatic optimizer statistics collection and the Automatic Segment Advisor. This data is included if the PDB is unplugged. Automatic SQL Tuning Advisor runs only in the CDB root. See the SQL Tuning Advisor row in this table for information about data collected by Automatic SQL Tuning Advisor. | See the appropriate row in this table for data visibility information about the following manageability features: automatic optimizer statistics collection, Optimizer Statistics Advisor, Automatic Segment Advisor, and Automatic SQL Tuning Advisor. |
Automatic Database Diagnostic Monitor (ADDM) ADDM can diagnose the performance of a CDB or PDB and determine how identified problems can be resolved. | ADDM executions occur in a PDB or in the CDB root. ADDM analyzes data using one of the following sources: AWR data stored inside the PDB through an AWR snapshot taken inside the PDBAWR data from a non-CDB, CDB root, or PDB that is imported into the AWR storage of a PDBAWR data stored in the root container through an AWR snapshot taken in root Before the start of the analysis, ADDM determines the source of the AWR data (PDB or CDB root) and applies the rules applicable to each data type. Note: Automatic ADDM for a PDB is enabled only when automatic snapshots are enabled for the PDB. | A common user whose current container is the CDB root can review results for the entire CDB. The ADDM results can include information about multiple PDBs. ADDM results related to a PDB are not included if the PDB is unplugged. The ADDM results cannot be viewed when the current container is a PDB. A user whose current container is a PDB can view ADDM results data for the current PDB only. The results exclude findings that apply to the CDB as a whole, for example, I/O problems relating to the buffer cache size. |
Automatic Optimizer Statistics Collection Automatic optimizer statistics collection gathers optimizer statistics for all schema objects in the database for which there are no statistics or only stale statistics. The statistics gathered by this task are used by the SQL query optimizer to improve the performance of SQL execution. | When an automatic optimizer statistics collection task gathers data for a PDB, it stores this data in the PDB. This data is included if the PDB is unplugged. | A common user whose current container is the CDB root can view optimizer statistics data for PDBs. A user whose current container is a PDB can view optimizer statistics data for the PDB only. |
Automatic Segment Advisor The Automatic Segment Advisor identifies segments that have space available for reclamation and makes recommendations on how to defragment those segments. | When Automatic Segment Advisor gathers data for a PDB, it stores this data in the PDB. This data is included if the PDB is unplugged. | A common user whose current container is the CDB root can view Automatic Segment Advisor data for PDBs. A user whose current container is a PDB can view the Automatic Segment Advisor data for the PDB only. |
Automatic Workload Repository (AWR) The AWR collects, processes, and maintains performance statistics for problem detection and self-tuning purposes. This data is stored in the database. The gathered data can be displayed in both reports and views. | AWR reports can be generated in the CDB root or in any PDB. AWR reports generated in the CDB root pertain to the entire CDB, while AWR reports generated when a PDB is the current container only pertain to that PDB. AWR data generated in the CDB root is stored in the CDB root. AWR data generated in a PDB is stored in the PDB. When a PDB is unplugged, AWR data stored in the CDB root is not included. When a PDB is unplugged, AWR data stored in the PDB is included. | A common user whose current container is the CDB root can view AWR data for the CDB root and for PDBs. A user whose current container is a PDB can view AWR data for the PDB only. |
Database Replay Database Replay is a feature of Oracle Real Application Testing. Database Replay captures the workload for a CDB or PDB and replays it exactly on a test database. | Capture files are always stored in operating system files, regardless of whether the capture and replay is at the CDB level or PDB level. | For CDB-level workloads, a common user whose current container is the CDB root can view database capture and replay information. For PDB-level workloads, a local or common PDB administrator with the SELECT_CATALOG_ROLE privilege can view this information in DBA_WORKLOAD_CAPTURES and DBA_WORKLOAD_REPLAYS . |
Optimizer Statistics Advisor Optimizer Statistics Advisor analyzes how statistics are being gathered and suggests changes that can be made to fine tune statistics collection. | Data related to a PDB is stored in the PDB for Optimizer Statistics Advisor. This data is included if the PDB is unplugged. | A common user whose current container is the CDB root can view Optimizer Statistics Advisor data for PDBs. A user whose current container is a PDB can view the Optimizer Statistics Advisor data for the PDB only. |
SQL Management Base (SMB) SMB stores statement logs, plan histories, SQL plan baselines, and SQL profiles in the data dictionary. | SMB data related to a PDB is stored in the PDB. The SMB data related to a PDB is included if the PDB is unplugged. | A common user whose current container is the CDB root can view SMB data for PDBs. A user whose current container is a PDB can view the SMB data for the PDB only. |
SQL Performance Analyzer (SPA) SPA can analyze the SQL performance impact of SQL tuning and other system changes. SPA is often used with Database Replay. | A common user whose current container is the CDB root can run SPA for any PDB. In this case, the SPA results data is stored in the CDB root and is not included if the PDB is unplugged. A user whose current container is a PDB can run SPA on the PDB. In this case, the SPA results data is stored in the PDB and is included if the PDB is unplugged. | A common user whose current container is the CDB root can view SPA results data for PDBs. A user whose current container is a PDB can view the SPA results data for the PDB only. |
SQL Tuning Sets (STS) An STS is a database object that includes one or more SQL statements along with their execution statistics and execution context, and could include a user priority ranking. You can use an STS to tune a group of SQL statements or test their performance using SPA. | An STS can be stored in the CDB root or in any PDB. If it is stored in the CDB root, then you can load SQL statements from any PDB into it. When a PDB is unplugged, an STS stored in the CDB root is not included, even if the STS contains SQL statements from the PDB. When a PDB is unplugged, an STS stored in the PDB is included. | A common user whose current container is the CDB root can view STS data stored in the CDB root only. A user whose current container is a PDB can view STS data for the PDB only. |
SQL Tuning Advisor SQL Tuning Advisor optimizes SQL statements that have been identified as high-load SQL statements. | Automatic SQL Tuning Advisor data is stored in the CDB root. It might have results about SQL statements executed in a PDB that were analyzed by the advisor, but these results are not included if the PDB is unplugged. A common user whose current container is the CDB root can run SQL Tuning Advisor manually for SQL statements from any PDB. When a statement is tuned, it is tuned in any container that runs the statement. A user whose current container is a PDB can also run SQL Tuning Advisor manually for SQL statements from the PDB. When SQL Tuning Advisor is run manually from a PDB, the results are stored in the PDB from which it is run. In this case, a statement is tuned only for the current PDB, and the results related to a PDB are included if the PDB is unplugged. | When SQL Tuning Advisor is run automatically, the results are visible only to a common user whose current container is the CDB root. These results cannot be viewed when the current container is a PDB. When SQL Tuning Advisor is run manually by a user whose current container is a PDB, the results are only visible to a user whose current container is that PDB. |
To run SPA or SQL Tuning Advisor for SQL statements from a PDB, a common user must have the following privileges:
- Common
SET CONTAINER
privilege or localSET CONTAINER
privilege in the PDB - The privileges required to execute the SQL statements in the PDB
To connect to the root using the SQL*Plus CONNECT command:
- Configure your environment so that you can open SQL*Plus.
- Start SQL*Plus with the
/NOLOG
argument:
sqlplus /nolog
- Issue a SQL*Plus
CONNECT
command to connect to the root, as shown in the following examples.
Connecting to the Root with a Local Connection
This example connects to the root in the local CDB as user SYSTEM
. SQL*Plus prompts for the SYSTEM
user password.
connect system
Connecting to the Root with Operating System Authentication
This example connects locally to the root with the SYSDBA
administrative privilege with operating system authentication.
connect / as sysdba
Connecting to the Root with a Net Service Name
Assume that clients are configured to have a net service name for the root in the CDB. For example, the net service name can be part of an entry in a tnsnames.ora
file.
This example connects as common user c##dba
to the database service designated by the net service name mycdb
. SQL*Plus prompts for the c##dba
user password.
connect c##[email protected]
Connecting to a PDB Using the SQL*Plus CONNECT Command
To connect to a PDB with the SQL*Plus CONNECT
command, you can use easy connect or a net service name.
To connect to a PDB, a user must be one of the following:
- A common user with a
CREATE
SESSION
privilege granted commonly or granted locally in the PDB - A local user defined in the PDB with
CREATE
SESSION
privilege
Only a user with SYSDBA
, SYSOPER
, SYSBACKUP
, or SYSDG
privilege can connect to a PDB that is in mounted mode.
To connect to a PDB using the SQL*Plus CONNECT command:
- Configure your environment so that you can open SQL*Plus.
- Start SQL*Plus with the
/NOLOG
argument:
sqlplus /nolog
- Issue a SQL*Plus
CONNECT
command using easy connect or a net service name to connect to the PDB.
Connecting to a PDB
Assume that clients are configured to have a net service name for each PDB that matches each PDB name. For example, the net service name can be part of an entry in a tnsnames.ora
file.
The following command connects to the sh
local user in the salespdb
PDB:
CONNECT [email protected]
The following command connects to the SYSTEM
common user in the salespdb
PDB:
CONNECT [email protected]
Switching to a Container Using the ALTER SESSION Statement
When you are connected to a container as a common user, you can switch to a different container and application service using the ALTER SESSION
statement.
You can use the following statement to switch to a different container and application service:
ALTER SESSION SET CONTAINER =
container_name[SERVICE =
service_name]
For container_name, specify one of the following:
CDB$ROOT
to switch to the CDB rootPDB$SEED
to switch to the PDB seed- A PDB name to switch to the PDB
When the current container is the root, you can view the names of the PDBs in a CDB by querying the DBA_PDBS
view.
For service_name, specify a service that is running in the PDB. You can list the services running in the containers of a CDB, excluding the CDB root, by issuing the following query with the CDB root as the current container:
COL NAME FORMAT A30
COL CON_NAME FORMAT A20
SELECT NAME,CON_NAME, CON_ID
FROM V$ACTIVE_SERVICES
WHERE UPPER(NAME) != CON_NAME
AND CON_ID !=1
ORDER BY CON_ID;
By default, when you switch to a container, the session uses the default service for the container. However, the default PDB service does not support all service attributes and features such as service metrics, Fast Application Notification (FAN), load balancing, Resource Manager, Transaction Guard, Application Continuity, and so on. It is best practice to use a nondefault service for the container by specifying SERVICE =
service_name, where service_name is the name of the service.
With this new capability, connection pools can switch the service, and, when needed the PDB, on a connection when a connection is borrowed from the pool. Starting with Oracle Database 12c Release 2 (12.2.0.1), connection pools support more than one database service with universal connection pools (UCPs). It can also be used standalone.
When switching to a service, applications can consolidate to a CDB, while keeping the database services identified, prioritized, measured, and highly available. Switching to a nondefault service provides the following benefits:
- It preserves the service attributes and features.
- It eliminates too many connection pools with too many connections serving these tenants.
- It allows applications to use more database services for workload control without consuming too many connection pools. Customers can identify and prioritize workloads using services without over sizing the database connections.
To switch to a container using the ALTER SESSION statement:
- In SQL*Plus, connect to a container as a common user with the required privileges.
- Check the current open mode of the container to which you are switching.
To check the current open mode of the root or a PDB, query the OPEN_MODE
column in the V$CONTAINERS
view when the current container is the root.
The open mode of the root imposes limitations on the open mode of PDBs. For example, the root must be open before any PDBs can be open. Therefore, you might need to change the open mode of the root before changing the open mode of a PDB.
- If you are switching to a specific service, then ensure that the service is running.
To check the active status of the service, query the V$ACTIVE_SERVICES
view when the current container is the CDB root.
If the service is not running, then use the SRVCTL utility or the DBMS_SERVICE
package to start the service.
- Run the
ALTER SESSION SET CONTAINER
statement and specify the container to which you want to switch.
Include the SERVICE
clause to switch to a specific application service.
The following examples switch to various containers using ALTER
SESSION
.
Switching to the PDB salespdb and Using the salesrep Service
ALTER SESSION SET CONTAINER = salespdb SERVICE = salesrep;
Switching to the PDB salespdb and Using the Default Service
ALTER SESSION SET CONTAINER = salespdb;
Switching to the CDB Root
ALTER SESSION SET CONTAINER = CDB$ROOT;
Switching to the PDB Seed
ALTER SESSION SET CONTAINER = PDB$SEED;
Switching Services Using a Dummy Service in the CDB Root
To design connection pooling that switches the container and the service, one method is to create a dummy service in the CDB root and set all required service attributes on this dummy service (for example, drain_timeout
, TAF or Application Continuity). The service attributes must match across the CDB root and the PDB. To use this method, complete the following steps:
- Connect to the dummy service when first creating the connection pool and when creating new connections.
- As services are added to each PDB, set the same attributes on these real services.
- When an application requires a connection, complete one of the following actions:
- Create a new connection to the dummy service, and switch to the PDB and service.
- Borrow a free connection in the pool and switch to the PDB and service.
You do not need to return to the CDB root when switching across PDBs.
You do not need to return to the CDB root when switching across PDBs.
Modifying a CDB at the System Level
You can set initialization parameters at the CDB level. In some cases, you can override these parameters at the PDB level.
The ALTER SYSTEM SET
statement dynamically sets an initialization parameter in one or more containers.
A CDB uses an inheritance model for initialization parameters in which PDBs inherit initialization parameter values from the root. In this case, inheritance means that the value of a specific parameter in the root applies to a specific PDB.
A PDB can override the root setting for some parameters. In such cases, a PDB has an inheritance property for each initialization parameter that is either true or false. The inheritance property is true for a parameter when the PDB inherits the root’s value for the parameter; otherwise, the property is false.
The inheritance property for some parameters must be true. For other parameters, when the current container is the PDB, you can change the inheritance property by running the ALTER SYSTEM SET
statement. If V$SYSTEM_PARAMETER.ISPDB_MODIFIABLE
is TRUE
for an initialization parameter, then the inheritance property can be false for the parameter.
When the current container is the root, the CONTAINER
clause of the ALTER SYSTEM SET
statement controls which PDBs inherit the parameter value being set. The CONTAINER
clause has the following syntax:
CONTAINER = { CURRENT | ALL }
The following settings are possible:
CURRENT
The parameter setting applies only to the current container. This is the default setting for CONTAINER
. When the current container is the root, the parameter setting applies to the root and to any PDB with an inheritance property of true for the parameter.
ALL
The parameter setting applies to all containers in the CDB, including the root and all PDBs. Specifying ALL
sets the inheritance property to true for the parameter in all PDBs.
Modifying a CDB with ALTER SYSTEM
To modify a CDB at the system level, use the ALTER SYSTEM
statement.
To use ALTER SYSTEM SET in the root in a CDB:
- In SQL*Plus, ensure that the current container is the root.
- Run the
ALTER SYSTEM SET
statement.
ALTER SYSTEM RESET OPEN_CURSORS SCOPE = SPFILE;
Setting an Initialization Parameter for All Containers
This ALTER SYSTEM SET
statement sets the OPEN_CURSORS
initialization parameter to 200
for the all containers and sets the inheritance property to TRUE
in each PDB.
ALTER SYSTEM SET OPEN_CURSORS = 200 CONTAINER = ALL;
Setting an Initialization Parameter for the Root
This ALTER SYSTEM SET
statement sets the OPEN_CURSORS
initialization parameter to 200
for the root and for PDBs with an inheritance property of true for the parameter.
ALTER SYSTEM SET OPEN_CURSORS = 200 CONTAINER = CURRENT;
Modifying Containers When Connected to the CDB Root
You can modify the entire CDB or the root with the ALTER DATABASE
statement.
The ALTER DATABASE
statement modifies a CDB. When you are connected to the CDB root, the ALTER PLUGGABLE DATABASE
statement can modify the open mode of one or more PDBs.
The behavior of ALTER DATABASE
and ALTER PLUGGABLE DATABASE
depends on which container you are connected to when you use the statement:
- Connected as a common user to CDB root
In this case, the ALTER DATABASE
statement works the same as in a non-CDB. When an ALTER DATABASE
statement with the RENAME GLOBAL_NAME
clause modifies the domain of a CDB, it affects the domain of each PDB with a domain that defaults to that of the CDB. The ALTER PLUGGABLE DATABASE
statement with the pdb_change_state clause modifies the open mode of one or more PDBs.
- Connected to a PDB
In this case, the ALTER DATABASE
and ALTER PLUGGABLE DATABASE
statements modify the current PDB only.
The following table lists which containers are modified by clauses in ALTER DATABASE
and ALTER PLUGGABLE DATABASE
statements.
Statements That Modify Containers in a CDB
Modify Entire CDB | Modify Root Only | Modify One or More PDBs |
When connected as a common user whose current container is the root, ALTER DATABASE statements with the following clauses modify the entire CDB: startup_clausesrecovery_clauseslogfile_clausescontrolfile_clausesstandby_database_clausesinstance_clausessecurity_clauseRENAME GLOBAL_NAME clauseENABLE BLOCK CHANGE TRACKING clauseDISABLE BLOCK CHANGE TRACKING clause | When connected as a common user whose current container is the root, ALTER DATABASE statements with the following clauses modify the root only: database_file_clausesDEFAULT EDITION clauseDEFAULT TABLESPACE clauseDEFAULT TEMPORARY TABLESPACE clause ALTER DATABASE statements with the following clauses modify the root and set default values for PDBs: flashback_mode_clauseSET DEFAULT {BIGFILE|SMALLFILE} TABLESPACE clauseset_time_zone_clause You can use these clauses to set nondefault values for specific PDBs. | When connected as a common user whose current container is the root, ALTER PLUGGABLE DATABASE statements with the following clause can modify the open mode of one or more PDBs: pdb_change_state When the current container is a PDB, ALTER PLUGGABLE DATABASE statements with this clause can modify the open mode of the current PDB. When connected as a common user whose current container is the root, ALTER PLUGGABLE DATABASE statements with the following clause can preserve or discard the open mode a PDB when the CDB restarts: pdb_save_or_discard_state |
Modifying an Entire CDB Using ALTER DATABASE
You can use the ALTER DATABASE
statement to modify an entire CDB, including the root and all PDBs. Most ALTER DATABASE
statements modify the entire CDB.
Prerequisites
To modify an entire CDB, the following prerequisites must be met:
- The current user must be a common user with the
ALTER DATABASE
privilege. - To use an
ALTER DATABASE
statement with a recovery_clause, the current user must have theSYSDBA
administrative privilege commonly granted. In this case, you must exercise this privilege usingAS SYSDBA
at connect time.
To modify an entire CDB:
- In SQL*Plus, ensure that the current container is the root.
- Use an
ALTER DATABASE
statement with a clause that modifies an entire CDB.
Backing Up the Control File for a CDB
The following ALTER DATABASE
statement uses a recovery_clause to back up a control file.
ALTER DATABASE BACKUP CONTROLFILE TO '+DATA/dbs/backup/control.bkp';
Adding a Redo Log File to a CDB
The following ALTER DATABASE
statement uses a logfile_clause to add redo log files.
ALTER DATABASE cdb ADD LOGFILE
GROUP 4 ('/u01/logs/orcl/redo04a.log','/u02/logs/orcl/redo04b.log')
SIZE 100M BLOCKSIZE 512 REUSE;
Setting the Undo Mode in a CDB Using ALTER DATABASE
When local undo is enabled, each container has its own undo tablespace for every instance in which it is open. When local undo is disabled, there is one undo tablespace for the entire CDB.
CDB Undo Mode
You can configure a CDB to use local undo in every container or to use shared undo (default) for the entire CDB.
A CDB runs either in local or shared undo mode. The undo mode applies to the entire CDB. Therefore, every container either uses shared undo or local undo.
You can specify the undo mode of a CDB during CDB creation in the ENABLE PLUGGABLE DATABASE
clause of the CREATE DATABASE
statement. If you do not specify the UNDO
clause, then shared undo mode is the default. You can change the undo mode of a CDB after it is created by issuing an ALTER DATABASE
statement and restarting the CDB.
To determine the current CDB undo mode, run the following query in the CDB root:
SELECT PROPERTY_NAME, PROPERTY_VALUE
FROM DATABASE_PROPERTIES
WHERE PROPERTY_NAME = 'LOCAL_UNDO_ENABLED';
If the query returns TRUE
for the PROPERTY_VALUE
, then the CDB is in local undo mode. Otherwise, the CDB is in shared undo mode.
Local Undo Mode
Local undo mode means that each container has its own undo tablespace for every instance in which it is open.
In this mode, Oracle Database automatically creates an undo tablespace for every container in the CDB. For an Oracle RAC CDB, there is one active undo tablespace for each instance for each PDB in local undo mode.
Local undo mode provides increased isolation for each container and improves the efficiency of some operations, such as unplugging the container or performing point-in-time recovery on the container. In addition, local undo mode is required for some operations to be supported, such as relocating a PDB or cloning a PDB that is in open read/write mode.
When a CDB is in local undo mode, the following applies:
- Any user who has the appropriate privileges for the current container can create an undo tablespace for the container.
- Undo tablespaces are visible in static data dictionary views and dynamic performance (V$) views in every container in the CDB.
Shared Undo Mode
Shared undo mode means that only one active undo tablespace exists for a single-instance CDB. For an Oracle RAC CDB, there is one active undo tablespace for each instance.
When a CDB is in shared undo mode, the following applies:
- Only a common user who has the appropriate privileges and whose current container is the CDB root can create an undo tablespace.
- When the current container is not the CDB root, an attempt to create an undo tablespace fails and returns an error.
- Undo tablespaces are visible in static data dictionary views and dynamic performance (V$) views when the current container is the CDB root. Undo tablespaces are visible only in dynamic performance views when the current container is a PDB, an application root, or an application PDB.
Configuring a CDB to Use Local Undo Mode
You can change a CDB to local undo mode by issuing an ALTER DATABASE LOCAL UNDO ON
statement and restarting the database.
When a CDB is in local undo mode, each container has its own undo tablespace for every instance in which it is open. Oracle Database automatically creates an undo tablespace in any container in the CDB that does not have one. If a PDB without an undo tablespace is cloned, relocated, or plugged into a CDB that is configured to use local undo mode, then Oracle Database automatically creates an undo tablespace for the PDB the first time it is opened.
When a CDB is changed from shared undo mode to local undo mode, Oracle Database creates the required undo tablespaces automatically.
- If the CDB instance is open, then shut it down.
- Start up the CDB instance in
OPEN UPGRADE
mode. For example:
STARTUP UPGRADE
- In SQL*Plus, ensure that the current container is the CDB root. For example, enter the following:
SHOW CON_NAME
CON_NAME
------------------------------
CDB$ROOT
- Query the current undo mode of the CDB:
SELECT PROPERTY_NAME, PROPERTY_VALUE
FROM DATABASE_PROPERTIES
WHERE PROPERTY_NAME = 'LOCAL_UNDO_ENABLED';
- To enable local undo, issue the following SQL statement:
ALTER DATABASE LOCAL UNDO ON;
- Shut down and restart the CDB instance.
- Optional: Manually create an undo tablespace in the PDB seed.
While Oracle Database creates an undo tablespace in the PDB seed automatically in local undo mode, you might want to control the size and configuration of the undo tablespace by creating an undo tablespace manually. To ensure the PDBs created from the PDB seed use the manually-created undo tablespace and not the automatically-created undo tablespace, you must set the UNDO_TABLESPACE
initialization parameter to the manually-created undo tablespace, or drop the automatically-created undo tablespace.
- In SQL*Plus, ensure that the current container is the root.
- Place the PDB seed in open read/write mode:
ALTER PLUGGABLE DATABASE PDB$SEED OPEN READ WRITE FORCE;
- Switch container to the PDB seed:
ALTER SESSION SET CONTAINER=PDB$SEED;
- Create an undo tablespace in the PDB seed. For example:
CREATE UNDO TABLESPACE seedundots1
DATAFILE 'seedundotbs_1a.dbf'
SIZE 10M AUTOEXTEND ON
RETENTION GUARANTEE;
- Switch container to the root:
ALTER SESSION SET CONTAINER=CDB$ROOT;
- Place the PDB seed in open read-only mode:
ALTER PLUGGABLE DATABASE PDB$SEED OPEN READ ONLY FORCE;
Configuring a CDB to Use Shared Undo Mode
To change a CDB to use shared undo mode, use an ALTER DATABASE LOCAL UNDO OFF
statement.
- If the CDB instance is open, then shut it down.
- Start up the CDB instance in
OPEN UPGRADE
mode. For example:
STARTUP UPGRADE
- In SQL*Plus, ensure that the current container is the CDB root. For example, enter the following:
SHOW CON_NAME
CON_NAME
------------------------------
CDB$ROOT
- Optionally, query the current undo mode of the CDB:
SELECT PROPERTY_NAME, PROPERTY_VALUE
FROM DATABASE_PROPERTIES
WHERE PROPERTY_NAME = 'LOCAL_UNDO_ENABLED';
- To turn off local undo, issue the following SQL statement:
ALTER DATABASE LOCAL UNDO OFF;
- Shut down and restart the CDB instance.
When in shared undo mode, the CDB ignores any local undo tablespaces that were created when it was in local undo mode. Oracle recommends that you delete the unused local undo tablespaces.
Modifying the CDB Root Using ALTER DATABASE
To modify only the root of a CDB, use the ALTER DATABASE
statement.
When the current container is the root, some ALTER DATABASE
statements modify the root without directly modifying any of the PDBs.
Some statements set the defaults for the PDBs in the CDB. You can overwrite these defaults for a PDB by using the ALTER PLUGGABLE DATABASE
statement.
Prerequisites
To modify the root, the current user must have the ALTER DATABASE
privilege in the root.
To modify the root:
- In SQL*Plus, ensure that the current container is the root.
- Run an
ALTER DATABASE
statement with a clause that modifies the root.
The following examples modify the root.
A user whose current container is the root that is not explicitly assigned a tablespace uses the default permanent tablespace for the root. The tablespace specified in the ALTER DATABASE
statement must exist in the root.
After executing this statement, the default type of subsequently created tablespaces in the root is bigfile. This setting is also the default for PDBs.
The tablespace or tablespace group specified in the ALTER DATABASE
statement must exist in the root.
Changing the Default Permanent Tablespace for the Root
This ALTER DATABASE
statement uses a DEFAULT TABLESPACE
clause to set the default permanent tablespace to root_tbs
for the root.
ALTER DATABASE DEFAULT TABLESPACE root_tbs;
Bringing a Data File Online for the Root
This ALTER DATABASE
statement uses a database_file_clause to bring the /u02/oracle/cdb_01.dbf data file online.
ALTER DATABASE DATAFILE '/u02/oracle/cdb_01.dbf' ONLINE;
Changing the Default Tablespace Type for the Root
This ALTER DATABASE
statement uses a SET DEFAULT TABLESPACE
clause to change the default tablespace type to bigfile for the root.
ALTER DATABASE SET DEFAULT BIGFILE TABLESPACE;
Changing the Default Temporary Tablespace for the Root
This ALTER DATABASE
statement uses a DEFAULT TEMPORARY TABLESPACE
clause to set the default temporary tablespace to root_temp
for the root.
ALTER DATABASE DEFAULT TEMPORARY TABLESPACE root_temp;
Executing SQL in a Different Container
To execute SQL in a different container, use the CONTAINERS
clause for DML or the CONTAINER
clause for DDL.
Issuing DML Statements on a Container in a CDB
A DML (data manipulation language) statement issued in a CDB or application root can modify a different container in the CDB. In addition, you can specify a default container target for DML statements.
DML statements can affect database objects in a specified container in a CDB.
The container is specified by container ID. Because the container ID can appear in more than one location, the database uses the following order of precedence:
- The
CON_ID
specified in theWHERE
clause of a DML statement - The
CONTAINERS_DEFAULT_TARGET
database property - The current container, which is either the CDB root or application root
In a CDB root or an application root, a DML statement that includes the CONTAINERS
clause can modify a table or view in a single container in the CDB or application container. To use the CONTAINERS
clause, specify the table or view being modified in the CONTAINERS
clause and the container ID affected in the WHERE
clause.
You can specify a target container in an INSERT VALUES
statement by specifying a value for CON_ID
in the VALUES
clause. Also, you can specify a target container in an UPDATE
or DELETE
statement by specifying a CON_ID
predicate in the WHERE
clause. For example, the following DML statement updates the sales.customers
table in the container with a CON_ID
of 7
:
UPDATE CONTAINERS(sales.customers) ctab
SET ctab.city_name='MIAMI'
WHERE ctab.CON_ID=7
AND CUSTOMER_ID=3425;
Specifying the Default Container for DML Statements in a CDB
To specify the default container for DML statements in a CDB, issue the ALTER DATABASE
statement with the CONTAINERS DEFAULT TARGET
clause.
When a DML statement is issued in a CDB root without specifying containers in the WHERE
clause, the DML statement affects the default container for the CDB. The default container can be any container in the CDB, including the CDB root, a PDB, an application root, or an application PDB. Only one default container is allowed.
The CONTAINERS_DEFAULT_TARGET
database property sets the default container. By default, this property is not set. You can determine the default target containers for a CDB by running the following query:
SELECT PROPERTY_VALUE
FROM DATABASE_PROPERTIES
WHERE PROPERTY_NAME='CONTAINERS_DEFAULT_TARGET';
- In SQL*Plus, ensure that the current container is the CDB root or application root.
The current user must have the commonly granted ALTER DATABASE
privilege.
- Run the
ALTER DATABASE
statement with theCONTAINERS DEFAULT TARGET
clause.
Specifying the Default Container for DML Statements in a CDB
This example specifies that PDB1
is the default container for DML statements in the CDB.
ALTER DATABASE CONTAINERS DEFAULT TARGET = (PDB1);
Clearing the Default Container
This example clears the default container setting. When it is not set, the default container is the CDB root.
ALTER DATABASE CONTAINERS DEFAULT TARGET = NONE;
Executing DDL Statements in a CDB
In a CDB, you can execute a data definition language (DDL) statement in the current container or in all containers.
In a CDB, some DDL statements can apply to all containers or to the current container only.
To specify which containers are affected, use the CONTAINER
clause:
CONTAINER = { CURRENT | ALL }
The following settings are possible:
CURRENT
means that the statement applies only to the current container.ALL
means that the statement applies to all containers in the CDB, including the root and all PDBs.
The following restrictions apply to the CONTAINER
clause in DDL statements:
- You can use the
CONTAINER
clause only with the DDL statements.
Statements and the CONTAINER Clause in a CDB
DDL Statement | CONTAINER = CURRENT | CONTAINER = ALL |
CREATE USER | Creates a local user in the current PDB. | Creates a common user. |
ALTER USER | Alters a local user in the current PDB. | Alters a common user. |
CREATE ROLE | Creates a local role in the current PDB. | Creates a common role. |
GRANT | Grants a privilege in the local container to a local user, common user, or local role. The SET CONTAINER privilege can be granted to a user-created common user in the current PDB. | Grants a system privilege or object privilege on a common object to a common user or common role. The specified privilege is granted to the user or role across the entire CDB. |
REVOKE | Revokes a privilege in the local container from a local user, common user, or local role. This statement can revoke only a privilege granted with CURRENT specified in the CONTAINER clause from the specified user or role in the local container. The statement does not affect privileges granted with ALL specified in the CONTAINER clause. The SET CONTAINER privilege can be revoked from a user-created common user in the current PDB. | Revokes a system privilege or object privilege on a common object from a common user or common role. The specified privilege is revoked from the user or role across the entire CDB. This statement can revoke only a privilege granted with ALL specified in the CONTAINER clause from the specified common user or common role. The statement does not affect privileges granted with CURRENT specified in the CONTAINER clause. However, any privileges granted locally that depend on the privilege granted commonly that is being revoked are also revoked. |
All other DDL statements apply to the current container only.
In addition to the usual rules for user, role, and profile names, the following rules and best practices apply when you create a user, role, or profile in a CDB:
- It is best practice for common user, role, and profile names to start with a prefix to avoid naming conflicts between common users, roles, and profiles and local users, roles, and profiles. You specify this prefix with the
COMMON_USER_PREFIX
initialization parameter in the CDB root. By default, the prefix isC##
orc##
in the CDB root. - In an application container, it is best practice for application common user, role, and profile names to start with a prefix to avoid naming conflicts between application common users, roles, and profiles and local users, roles, and profiles. You specify this prefix with the
COMMON_USER_PREFIX
initialization parameter in the application root. By default, the prefix isNULL
in an application root. - When the
COMMON_USER_PREFIX
initialization parameter is set in an application root, the setting applies to the application common user, role, and profile names in the application container. The prefix can be different in the CDB root and in an application root, and the prefix can be different in different application containers. - Common user, role, and profile names must consist only of ASCII characters. This restriction does not apply to application common user, role, and profile names.
- Local user, role, and profile names cannot start with the prefix specified for common users with the
COMMON_USER_PREFIX
initialization parameter. - Local user, role, and profile names cannot start with
C##
orc##
. - Regardless of the value of
COMMON_USER_PREFIX
in the CDB root, application common user, role, and profile names cannot start withC##
orc##
. - Application common user, role, and profile names cannot start with the prefix specified for common users with the
COMMON_USER_PREFIX
initialization parameter.
Executing a DDL Statement in the Current Container
Specify CURRENT
in the CONTAINER
clause of a DDL statement to execute the statement in the current container.
The current user must be granted the required privileges to execute the DDL statement in the current container. For example, to create a user, the current user must be granted the CREATE USER
system privilege in the current container.
To execute a DDL statement in the current container:
- In SQL*Plus, access a container.
- Execute the DDL statement with
CONTAINER
set toCURRENT
.
A local user’s user name cannot start with the prefix specified by the COMMON_USER_PREFIX
initialization parameter. By default, in the CDB root, the prefix is C##
or c##
. An application root can specify its own prefix for an application container. In addition, a common user’s name must consist only of ASCII characters. The specified tablespace must exist in the PDB.
Creating Local User in a PDB
This example creates the local user testpdb
in the current PDB.
CREATE USER testpdb IDENTIFIED BY
password
DEFAULT TABLESPACE pdb1_tbs
QUOTA UNLIMITED ON pdb1_tbs
CONTAINER = CURRENT;
Executing a DDL Statement in All Containers in a CDB
Specify ALL
in the CONTAINER
clause of a DDL statement to execute the statement in all containers in a CDB.
To execute a DDL statement in all containers in a CDB:
- In SQL*Plus, ensure that the current container is the root.
- Execute the DDL statement with
CONTAINER
set toALL
.
A common user’s user name must start with the prefix specified by the COMMON_USER_PREFIX
initialization parameter. By default, in the CDB root, the prefix is C##
or c##
. An application root can specify its own prefix for an application container. In addition, a common user’s name must consist only of ASCII characters. The specified tablespace must exist in the root and in all PDBs.
Creating Common User in a CDB
This example creates the common user c##testcdb
.
CREATE USER c##testcdb IDENTIFIED BY
password
DEFAULT TABLESPACE cdb_tbs
QUOTA UNLIMITED ON cdb_tbs
CONTAINER = ALL;
Running Oracle-Supplied SQL Scripts in a CDB
You can use the catcon.pl
script to run Oracle-supplied SQL or SQL scripts within a CDB. You can run the script against any specified containers.
In a CDB, the catcon.pl
script is the best way to run SQL scripts and SQL statements.
An Oracle Database installation includes several SQL scripts. These scripts perform operations such as creating data dictionary views and installing options.
The catcon.pl
script can run scripts in the root and in specified PDBs in the correct order, and it generates log files that you can view to confirm that the SQL script or SQL statement did not generate unexpected errors. It also starts multiple processes and assigns new scripts to them as they finish running scripts previously assigned to them.
Syntax and Parameters for catcon.pl
The catcon.pl
script is a Perl script that must be run at an operating system prompt.
The catcon.pl
script has the following syntax and parameters:
$ORACLE_HOME/perl/bin/perl $ORACLE_HOME/rdbms/admin/catcon.pl
[--usr
username[/
password]]
[--int_usr
username[/
password]]
[--script_dir
directory]
[--log_dir
directory]
[{--incl_con|--excl_con}
container]
[--echo]
[--spool]
[--error_logging { ON | errorlogging-table-other-than-SPERRORLOG } ]
[--app_con
application_root]
[--no_set_errlog_ident]
[--diag]
[-ignore_unavailable_pdbs]
[--verbose]
[--force_pdb_mode
pdb_mode]
[--recover]
--log_file_base
log_file_name_base
-- {
SQL_script[
arguments] | --x'
SQL_statement' }
Ensure that --x
SQL_statement is preceded by --
if it follows any single-letter parameter. If --x
SQL_statement is preceded by a script name or another --x
SQL_statement, then do not precede it with --
. Also, note that the SQL statement must be inside single quotation marks.
Command line parameters to SQL scripts can be introduced using --p
. Interactive (or secret) parameters to SQL scripts can be introduced using --P
.
To view the help for the catcon.pl
script, change directories to $ORACLE_HOME/perl/bin/
, and then run the following command:
perl $ORACLE_HOME/rdbms/admin/catcon.pl --help
The following table describes the catcon.pl
parameters. A parameter is optional unless it is indicated that it is required.
The short parameter names in the following table are for backward compatibility. Some parameters do not have short names.
catcon.pl Parameters
Parameter | Short Name | Description |
--usr | -u | Specifies the user name and password to connect to the root and the specified PDBs. Specify a common user with the required privileges to run the SQL script or the SQL statement. The default is “/ AS SYSDBA “. If no password is supplied, then catcon.pl prompts for a password. |
--int_usr | -U | Specifies the user name and password to connect to the root and the specified PDBs. Specify a common user with the required privileges to perform internal tasks, such as querying CDB metadata. The default is / AS SYSDBA . If no password is supplied, then catcon.pl prompts for a password. |
--script_dir | -d | Directory that contains the SQL script. The default is the current directory. |
--log_dir | -l | Directory into which catcon.pl writes log files. The default is the current directory. |
{--incl_con|--excl_con} | {-c|-C} | The containers in which the SQL script is run or is not run. The --incl_con parameter lists the containers in which the SQL script is run. The --excl_con parameter lists the containers in which the SQL script is not run. Specify containers in a space-delimited list of PDB names enclosed in single quotation marks. The --incl_con and --excl_con parameters are mutually exclusive. When this parameter is used, the --app_con parameter cannot be used. |
--echo | -e | Sets echo ON while running the script. The default is echo OFF . |
--spool | -s | Spools the output of every script into a file with the following name: log-file-name-base_script-name-without-extension_[ container-name-if-any]. default-extension |
--error_logging | -E | When set to ON , the default error logging table is used. ON is the default setting. When set to ON , errors are written to the table SPERRORLOG in the current schema in each container in which the SQL script runs. If this table does not exist in a container, then it is created automatically. When a table other than SPERRORLOG is specified, errors are written to the specified table. The table must exist in each container in which the SQL script runs, and the current user must have the necessary privileges to perform DML operations on the table in each of these containers. |
--app_con | -F | Specify an application root. The scripts are run in the application root and in the application PDBs that are plugged into the application root. When this parameter is used, the --incl_con and --excl_con parameters cannot be used. |
--no_set_errlog_ident | -I | Do not issue a SET ERRORLOGGING identifier. This option is intended for cases in which the SET ERRORLOGGING identifier is already set and should not be overwritten. |
--diag | -g | Turns on the generation of debugging information. |
--verbose | -v | Turns on verbose output. |
--ignore_unavailable_pdbs | -f | Ignore PDBs that are closed or, if the --incl_con or --excl_con option is used, do not exist and process only open PDBs that were specified explicitly or implicitly. When this option is not specified and some specified PDBs do not exist or are not open, an error is returned and none of the containers are processed. |
--force_pdb_mode | n/a | The required open mode for all PDBs against which the scripts are run. Specify one of the following values: UNCHANGED READ WRITE READ ONLY UPGRADE DOWNGRADE When a value other than UNCHANGED is specified, all of the PDBs against which the script is run are changed to the specified open mode. If a PDB is open in a different mode, then the PDB is closed and re-opened in the specified mode. After all of the scripts are run, each PDB is restored to its original open mode. When UNCHANGED , the default, is specified, the open mode of the PDBs is not changed. |
--recover | -R | Causes catcon.pl to attempt to recover if a SQL*Plus process that it spawned ends unexpectedly. When this parameter is not specified, catcon.pl does not attempt to recover the process and closes. |
--log_file_base | -b | (Required) The base name for log file names. |
Running the catcon.pl Script
Examples illustrate running the catcon.pl
script.
If a SQL script or SQL statement run by catcon.pl
performs data manipulation language (DML) or data definition language (DDL) operations, then the containers being modified must be in read/write mode.
To run the catcon.pl script:
- Open a command line prompt.
- Run the
catcon.pl
script and specify one or more SQL scripts or SQL statements:
cd $ORACLE_HOME/perl/bin/
perl $ORACLE_HOME/rdbms/admin/catcon.pl
parametersSQL_script
perl $ORACLE_HOME/rdbms/admin/catcon.pl
parameters-- --x
SQL_statement
Running the catblock.sql Script in All Containers in a CDB
The following example runs the catblock.sql
script in all of the containers of a CDB (the backslash indicates line continuation):
$ORACLE_HOME/perl/bin/perl $ORACLE_HOME/rdbms/admin/catcon.pl \
--usr SYS --script_dir $ORACLE_HOME/rdbms/admin \
--log_file_base catblock_output catblock.sql
The following parameters are specified:
- The
--usr
parameter specifies thatSYS
user runs the script in each container. - The
--script_dir
parameter specifies that the SQL script is in the$ORACLE_HOME/rdbms/admin
directory. - The
--log_file_base
parameter specifies that the base name for log file names iscatblock_output
.
Default parameter values are used for all other parameters. Neither the --incl_con
nor the --excl_con
parameter is specified. Therefore, catcon.pl runs the script in all containers by default.
Running the catblock.sql Script in Specific PDBs
The following example runs the catblock.sql
script in the hrpdb
and salespdb
PDBs in a CDB.
$ORACLE_HOME/perl/bin/perl $ORACLE_HOME/rdbms/admin/catcon.pl \
--usr SYS --int_usr SYS --script_dir $ORACLE_HOME/rdbms/admin \
--log_dir '/disk1/script_output' --incl_con 'HRPDB SALESPDB' \
--log_file_base catblock_output catblock.sql
The following parameters are specified:
- The
--usr
parameter specifies thatSYS
user runs the script in each container. - The
--int_usr
parameter specifies thatSYS
user performs internal tasks. - The
--script_dir
parameter specifies that the SQL script is in the$ORACLE_HOME/rdbms/admin
directory. - The
--log_dir
parameter specifies that the output files are placed in the/disk1/script_output
directory. - The
--incl_con
parameter specifies that the SQL script is run in thehrpdb
andsalespdb
PDBs. The script is not run in any other containers in the CDB. - The
--log_file_base
parameter specifies that the base name for log file names iscatblock_output
.
Running the catblock.sql Script in All Containers Except for Specific PDBs
The following example runs the catblock.sql
script in all of the containers in a CDB except for the hrpdb
and salespdb
PDBs.
$ORACLE_HOME/perl/bin/perl $ORACLE_HOME/rdbms/admin/catcon.pl \
--usr SYS --script_dir $ORACLE_HOME/rdbms/admin \
--log_dir '/disk1/script_output' --excl_con 'HRPDB SALESPDB' \
--log_file_base catblock_output catblock.sql
The following parameters are specified:
- The
--usr
parameter specifies thatSYS
user runs the script in each container. - The
--script_dir
parameter specifies that the SQL script is in the$ORACLE_HOME/rdbms/admin
directory. - The
--log_dir
parameter specifies that the output files are placed in the/disk1/script_output
directory. - The
--excl_con
parameter specifies that the SQL script is run in all of the containers in the CDB except for thehrpdb
andsalespdb
PDBs. - The
--log_file_base
parameter specifies that the base name for log file names iscatblock_output
.
Running a SQL Script with Command Line Parameters
The following example runs the custom_script.sql
script in all of the containers of a CDB.
cd $ORACLE_HOME/perl/bin/
perl $ORACLE_HOME/rdbms/admin/catcon.pl --usr SYS --script_dir /u01/scripts \
--log_file_base custom_script_output custom_script.sql '--phr' \
'--PEnter password for user hr:'
The following parameters are specified:
- The
--usr
parameter specifies thatSYS
user runs the script in each container. - The
--script_dir
parameter specifies that the SQL script is in the /u01/scripts directory. - The
--log_file_base
parameter specifies that the base name for log file names iscustom_script_output
. - The
--p
parameter specifieshr
for a command line parameter - The
--P
parameter specifies an interactive parameter that prompts for the password of userhr
.
Default parameter values are used for all other parameters. Neither the -incl_con
nor the -excl_con
parameter is specified. Therefore, catcon.pl runs the script in all containers by default.
Running a SQL Statement in All Containers in a CDB
The following example runs a SQL statement in all of the containers of a CDB.
cd $ORACLE_HOME/perl/bin/
perl $ORACLE_HOME/rdbms/admin/catcon.pl --usr SYS --echo \
--log_file_base select_output -- --x"SELECT * FROM DUAL"
The following parameters are specified:
- The
--usr
parameter specifies thatSYS
user runs the script in each container. - The
--echo
parameter shows output for the SQL statement. - The
--log_file_base
parameter specifies that the base name for log file names isselect_output
. - The SQL statement
SELECT * FROM DUAL
is inside quotation marks and is preceded by--x
. Because--x
is preceded by a parameter (--log_file_base
), it must be preceded by--
.
Default parameter values are used for all other parameters. Neither the -incl_con
nor the -excl_con
parameter is specified. Therefore, catcon.pl runs the SQL statement in all containers by default.
Executing Code in Containers Using the DBMS_SQL Package
When you are executing PL/SQL code in a container in a CDB, and you want to execute one or more SQL statements in a different container, use the DBMS_SQL
package to switch containers.
For example, you can use the DBMS_SQL
package to switch containers when you need to perform identical actions in more than one container.
The following are considerations for using DBMS_SQL
to switch containers:
- A transaction cannot span multiple containers.
If the set of actions you must perform in the target container requires a transaction, then consider using an autonomous transaction and perform a commit or rollback as the last action.
SET
ROLE
statements are not allowed.
Performing Identical Actions in More Than One Container
This example includes a PL/SQL block that creates the identact
table in the hr
schema in two PDBs (pdb1
and pdb2
). The example also inserts a row into the identact
table in both PDBs.
DECLARE
c1 INTEGER;
rowcount INTEGER;
taskList VARCHAR2(32767) :=
'DECLARE
PRAGMA AUTONOMOUS TRANSACTION;
BEGIN
-- Create the hr.identact table.
EXECUTE IMMEDIATE
''CREATE TABLE hr.identact
(actionno NUMBER(4) NOT NULL,
action VARCHAR2 (10))'';
EXECUTE IMMEDIATE
''INSERT INTO identact VALUES(1, 'ACTION1')'';
-- A commit is required if the tasks include DML.
COMMIT;
EXCEPTION
WHEN OTHERS THEN
-- If there are errors, then drop the table.
BEGIN
EXECUTE IMMEDIATE ''DROP TABLE identact'';
EXCEPTION
WHEN OTHERS THEN
NULL;
END;
END;';
TYPE containerListType IS TABLE OF VARCHAR2(128) INDEX BY PLS_INTEGER;
containerList containerListType;
BEGIN
containerList(1) := 'PDB1';
containerList(2) := 'PDB2';
c1 := DBMS_SQL.OPEN_CURSOR;
FOR conIndex IN containerList.first..containerList.last LOOP
DBMS_OUTPUT.PUT_LINE('Creating in container: ' || containerList(conIndex));
DBMS_SQL.PARSE(
c => c1 ,
statement => taskList,
language_flag => DBMS_SQL.NATIVE,
edition => NULL,
apply_crossedition_trigger => NULL,
fire_apply_trigger => NULL,
schema => 'HR',
container => containerList(conIndex));
rowcount := DBMS_SQL.EXECUTE(c=>c1);
END LOOP;
DBMS_SQL.CLOSE_CURSOR(c=>c1);
END;
/
Shutting Down a CDB Instance
You can shut down a CDB instance in the same way that you shut down a non-CDB instance.
Prerequisites
The following prerequisites must be met:
- The CDB instance must be mounted or open.
- The current user must be a common user with
SYSDBA
,SYSOPER
,SYSBACKUP
, orSYSDG
administrative privilege. To shut down a CDB, you must exercise this privilege usingAS
SYSDBA
,AS
SYSOPER
,AS
SYSBACKUP
, orAS
SYSDG
, respectively, at connect time.