Replication Rule Application

This section provides additional explanation and examples of usage for different combinations of replication filtering options.

Some typical combinations of replication filter rule types are given in the following table:

Condition (Types of Options)Outcome
No --replicate-* options at all:The slave executes all events that it receives from the master.
--replicate-*-db options, but no table options:The slave accepts or ignores events using the database options. It executes all events permitted by those options because there are no table restrictions.
--replicate-*-table options, but no database options:All events are accepted at the database-checking stage because there are no database conditions. The slave executes or ignores events based solely on the table options.
A combination of database and table options:The slave accepts or ignores events using the database options. Then it evaluates all events permitted by those options according to the table options. This can sometimes lead to results that seem counterintuitive, and that may be different depending on whether you are using statement-based or row-based replication; see the text for an example.

A more complex example follows, in which we examine the outcomes for both statement-based and row-based settings.

Suppose that we have two tables mytbl1 in database db1 and mytbl2 in database db2 on the master, and the slave is running with the following options (and no other replication filtering options):

replicate-ignore-db = db1
replicate-do-table  = db2.tbl2

Now we execute the following statements on the master:

USE db1;
INSERT INTO db2.tbl2 VALUES (1);

The results on the slave vary considerably depending on the binary log format, and may not match initial expectations in either case.

Statement-based replication.  The USE statement causes db1 to be the default database. Thus the --replicate-ignore-db option matches, and the INSERT statement is ignored. The table options are not checked.

Row-based replication.  The default database has no effect on how the slave reads database options when using row-based replication. Thus, the USE statement makes no difference in how the --replicate-ignore-db option is handled: the database specified by this option does not match the database where the INSERT statement changes data, so the slave proceeds to check the table options. The table specified by --replicate-do-table matches the table to be updated, and the row is inserted.

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