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https://dev.mysql.com/doc/refman/8.4/en/set-variable.html
A SET statement that assigns variable values is not written to the binary log, so in replication scenarios it affects only the host on which you execute it. To affect all replication hosts, execute the statement on each host. Many system variables ...variable: { user_var_name | param_name | local_var_name | {GLOBAL | @@GLOBAL.} system_var_name | {PERSIST | @@PERSIST.} system_var_name | {PERSIST_ONLY | @@PERSIST_ONLY.} system_var_name | [SESSION | ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-change-buffer.html
The change buffer is a special data structure that caches changes to secondary index pages when those pages are not in the buffer pool. Figure 17.3 Change Buffer Unlike clustered indexes, secondary indexes are usually nonunique, and inserts into ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-tips.html
Safe-updates mode is helpful for cases when you might have issued an UPDATE or DELETE statement but forgotten the WHERE clause indicating which rows to modify. Normally, such statements update or delete all rows in the table. Safe-updates mode also ... This section provides information about techniques for more effective use of mysql and about mysql operational ...
https://dev.mysql.com/doc/connectors/en/connector-odbc-reference-api.html
The following tables list Connector/ODBC API calls grouped by task: Table 5.5 ODBC API Calls for Connecting to a Data Source Function Name Connector/ODBC Supports? Standard Purpose SQLAllocHandle Yes ISO 92 Obtains an environment, connection, ...For ...
https://dev.mysql.com/doc/connector-odbc/en/connector-odbc-reference-api.html
The following tables list Connector/ODBC API calls grouped by task: Table 7.1 ODBC API Calls for Connecting to a Data Source Function Name Connector/ODBC Supports? Standard Purpose SQLAllocHandle Yes ISO 92 Obtains an environment, connection, ...For ...
https://dev.mysql.com/doc/refman/8.4/en/grant-tables.html
Modifications occur indirectly when you use account-management statements such as CREATE USER, GRANT, and REVOKE to set up accounts and control the privileges available to each one. When you use such statements to perform account manipulations, the ... The mysql system database includes several grant tables that contain information about user accounts and the privileges held by ...
https://dev.mysql.com/doc/refman/8.4/en/switchable-optimizations.html
Index Condition Pushdown Flags index_condition_pushdown (default on) Controls index condition pushdown. Index Extensions Flags use_index_extensions (default on) Controls use of index extensions. Index Merge Flags index_merge (default on) Controls ...
https://dev.mysql.com/doc/refman/8.4/en/miscellaneous-functions.html
Given this statement: CREATE TABLE t AS SELECT INET6_NTOA(expr) AS c1; The resulting table would have this definition: CREATE TABLE t (c1 VARCHAR(39) CHARACTER SET utf8mb3 DEFAULT NULL); The return string uses lowercase letters for IPv6 addresses.
https://dev.mysql.com/doc/refman/8.4/en/replication-gtids-lifecycle.html
MySQL appends a statement to the transaction to insert the GTID into the table. This operation is atomic for DDL statements as well as for DML statements. If binary logging is enabled on the replica, the filtered-out transaction is written to the ...
https://dev.mysql.com/doc/workbench/en/wb-tutorial-visual-explain-dbt3.html
After reviewing the query again, consider that a multiple-column index can meet the conditions of the WHERE clause that is based on both the o_orderdate and o_clerk columns as the next statement shows. Next, an Explain report was generated by ...