Program Option Modifiers Some options are “boolean” and control behavior that can be turned on or off. For example, the mysql client supports a --column-names [260] option that determines whether or not to display a row of column names at the beg...
Query Cache Probes The query cache probes are fired when executing any query. The query-cache-hit query is triggered when a query exists in the query cache and can be used to return the query cache information. The arguments contain the original query text and the number of rows returned from the...
Query Parsing Probes The query parsing probes are triggered before the original SQL statement is parsed and when the parsing of the statement and determination of the execution model required to process the statement has been completed: query-parse-start(query) query-parse-done(status) • query...
Removed Features The following constructs are obsolete and have been removed in MySQL 5.6. Where alternatives are shown, applications should be updated to use them. • The --log server option and the log system variable. Instead, use the --general_log [500] option to enable the general query log ...
Replication • As of MySQL 5.6, the relay-log.info file contains a line count and a replication delay value, so the file format differs from that in older versions. See Section 16.2.2.2, “Slave Status Logs”. If you downgrade a slave server to a...
Running Multiple MySQL Instances on One Machine In some cases, you might want to run multiple instances of MySQL on a single machine. You might want to test a new MySQL release while leaving an existing production setup undisturbed. Or you might want to give different users access to different my...
Running MySQL in ANSI Mode You can tell mysqld to run in ANSI mode with the --ansi [428] startup option. Running the server in ANSI mode is the same as starting it with the following options: --transaction-isolation=SERIALIZABLE --sql-mode=ANSI You can achieve the same effect at runtime by execu...
Secondary Indexes • Create secondary indexes: CREATE INDEX name ON table (col_list) or ALTER TABLE table ADD INDEX name (col_list). (Creating a a FULLTEXT index still requires locking the table....
Security improvements. These security improvements were made: • MySQL now provides a method for storing authentication credentials encrypted in an option file named .mylogin.cnf. To create the file, use the mysql_config_editor utility. The file can be read later by MySQL client programs to obtain...
SELECT INTO TABLE Differences MySQL Server doesn't support the SELECT ... INTO TABLE Sybase SQL extension. Instead, MySQL Server supports the INSERT INTO ... SELECT standard SQL syntax, which is basically the same thing. See Section 13.2.5.1, “IN...
