5.1 Using CDB Root Capture from PDB
To capture from a multitenant database, you must use an Extract that is
configured at the root level using a
c## account. To apply data
into a multitenant database, a separate Replicat is needed for each PDB, because a
Replicat connects at the PDB level and doesn't have access to objects outside of
One Extract group can capture from multiple pluggable databases to a single trail. In the parameter file, source objects must be specified in
SEQUENCE statements with their fully qualified three-part names in the format of
As an alternative to specifying three-part names, you can specify a default pluggable database with the
SOURCECATALOG parameter, and then specify only the
schema.object in subsequent
SEQUENCE parameters. You can use multiple instances of this configuration to handle multiple source pluggable databases. For example:
SOURCECATALOG pdb1 TABLE phoenix.tab; SEQUENCE phoenix.seq; SOURCECATALOG pdb2 TABLE dallas.tab; SEQUENCE dallas.seq;
5.1.1 Applying to Pluggable Databases
Replicat can only connect and apply to one pluggable database. To specify the correct one, use a SQL*Net connect string for the database user that you specify with the
USERIDALIAS parameter. For example:
GGADMIN@FINANCE. In the parameter file, specify only the
schema.object in the
TARGET portion of the
MAP statements. In the
MAP portion, identify source objects captured from more than one pluggable database with their three-part names or use the
SOURCECATALOG parameter with two-part names. The following is an example of this configuration.
SOURCECATALOG pdb1 MAP schema_1.tab, TARGET 1; MAP schema_1.seq, TARGET 1; SOURCECATALOG pdb2 MAP schema_2.tab, TARGET 2; MAP schema_2.seq, TARGET 2;
The following is an example without the use of
SOURCECATALOG to identify the source pluggable database. In this case, the source objects are specified with their three-part names.
MAP pdb1.schema_1.tab, TARGET 1; MAP pdb1.schema_1.seq, TARGET 1;
To configure replication from multiple source pluggable databases to multiple target pluggable databases, you can configure parallel Extract and Replicat streams, each handling data for one pluggable database. Alternatively, you can configure one Extract capturing from multiple source pluggable databases, which writes to one trail that is read by multiple Replicat groups, each applying to a different target pluggable database. Yet another alternative is to use one Extract writing to multiple trails, each trail read by a Replicat assigned to a specific target pluggable database :
5.2 Mining Mode Toggling
Mining mode toggling is not supported. This implies that after you create mining in
ROOT, then the session will stay mining in
and if the you choose to create mining in PDB, then the session will stay mining in that
CDB$ROOTto mining in specific PDB, then there is a migration process that you can follow:
Register a new per-PDB Extract. For example, the SCN returned is
Let the old
ROOTExtract mine the past
Stop the old Extract
Alter the new Extract so that its current SCN is set to be
Start the new Extract.
This new Extract picks up from where the old Extract left off.
Note:There may be some duplicate transactions at SCN
Y, if there were multiple
txscommitting at the same SCN
Y. However, Replicat can handle duplicate
5.3 Other Requirements for Multitenant Container Databases
This topic describes the special requirements that apply to replication to and from multitenant container databases.
The requirements are:
The different pluggable databases in the multitenant container database can have different character sets. Oracle GoldenGate captures data from any multitenant database with different character sets into one trail file and replicates the data without corruption due to using different character sets.
Extract must connect to the root container (
cdb$root) as a common user in order to interact with the logmining server. To specify the root container, use the appropriate SQL*Net connect string for the database user that you specify with the
USERIDALIASparameter. For example:
C##GGADMIN@FINANCE. See Establishing Oracle GoldenGate Credentials for how to create a user for the Oracle GoldenGate processes and grant the correct privileges.
To support source CDB 12.2, Extract must specify the trail format as release 12.3. Due to changes in the redo logs, to capture from a multitenant database that is Oracle 12.2 or higher, the trail format release must be 12.3 or higher.
dbms_goldengate_auth.grant_admin_privilegepackage grants the appropriate privileges for capture and apply within a multitenant container database. This includes the
containerparameter, which must be set to
ALL, as shown in the following example:
DDL replication works as a normal replication for multitenant databases. However, DDL on the root container should not be replicated because Replicats must not connect to the root container, only to PDBs.
FLUSH SEQUENCE for Multitenant Database
FLUSH SEQUENCE must be issued at the PDB level, so the user will
need to create an Oracle GoldenGate user in each PDB that they wish to do sequence
replication for, and then use
DBLOGIN to log into that PDB, and
then perform the
FLUSH SEQUENCE command.
It is recommended that you use the same schema in each PDB, so that it
works with the
GGSCHEMA GLOBALS parameter file. Here is an example:
Environment Information OGG 18.1 Oracle 12c to Oracle 12c Replication, Integrated Extract, Parallel Replicat Source: CDB GOLD, PDB CERTMISSN Target: CDB PLAT, PDB CERTDSQ Source OGG Configuration Container User: C##GGADMIN PDB User for Sequences: GGATE sqlplus / as sysdbao SQL> alter session set container=CERTMISSN; SQL> create user ggate identified by password default tablespace users temporary tablespace temp quota unlimited on users container=current;
Run @sequence sqlplus / as sysdba SQL> alter session set container=CERTMISSN; SQL> @sequence
GGATE GLOBALS GGSCHEMA GGATE
GGSCI> DBLOGIN USERIDALIAS GGADMIN DOMAIN GOLD_QC_CDB$ROOT GGSCI> FLUSH SEQUENCE CERTMISSN.SRCSCHEMA1.*
PDB User: GGATE Run @sequence sqlplus / as sysdba SQL> alter session set container=CERTDSQ; SQL> @sequence
When prompted enter
This also applies to the
@sequence.sql script, which must also be
run at each PDB that you are going to capture from.