sql_mode is also replicated
except for the
However, when mysqlbinlog parses a
SET @@sql_mode =
statement, the full
mode value, including
NO_DIR_IN_CREATE, is passed to
the receiving server.
variable is not replicated, regardless of the logging mode; this
is intended to facilitate replication between different storage
read_only system variable
is not replicated. In addition, the enabling this variable has
different effects with regard to temporary tables, table
locking, and the
statement in different MySQL versions.
variable is not replicated. Increasing the value of this
variable on the master without doing so on the slave can lead
eventually to Table is full errors on the
slave when trying to execute
INSERT statements on a
MEMORY table on the master that is
thus permitted to grow larger than its counterpart on the slave.
For more information, see
Section 18.104.22.168, “Replication and MEMORY Tables”.
Starting from MySQL 5.0.3 (master and slave), replication works even if the master and slave have different global character set variables. Starting from MySQL 5.0.4 (master and slave), replication works even if the master and slave have different global time zone variables.
Session variables are not replicated properly when used in statements that update tables. For example, the following sequence of statements will not insert the same data on the master and the slave:
SET max_join_size=1000; INSERT INTO mytable VALUES(@@max_join_size);
This does not apply to the common sequence, which replicates correctly as of MySQL 5.0.4.
SET time_zone=...; INSERT INTO mytable VALUES(CONVERT_TZ(..., ..., @@time_zone));
Update statements that refer to user-defined variables (that is,
variables of the form
replicated correctly in MySQL 5.0. However, this is
not true for versions prior to 4.1. Note that user variable
names are case insensitive starting in MySQL 5.0. You should
take this into account when setting up replication between MySQL
5.0 and older versions.
In MySQL 5.0.46 and later, the following session variables are written to the binary log and honored by the replication slave when parsing the binary log, regardless of the logging format:
Even though session variables relating to character sets and collations are written to the binary log, replication between different character sets is not supported.
It is strongly recommended that you always use the same setting
system variable on both master and slave. In particular, when a
case-sensitive file system is used, and this variable set to 1
on the slave, but to a different value on the master, names of
databases are not converted to lowercase, which can cause
replication to fail. This is a known issue, which is fixed in