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https://dev.mysql.com/doc/refman/8.4/en/insert.html
For example, without IGNORE, a row that duplicates an existing UNIQUE index or PRIMARY KEY value in the table causes a duplicate-key error and the statement is aborted. SET forms of the statement insert rows based on explicitly specified values.
https://dev.mysql.com/doc/refman/8.4/en/innodb-locks-set.html
A locking read, an UPDATE, or a DELETE generally set record locks on every index record that is scanned in the processing of an SQL statement. If you have no indexes suitable for your statement and MySQL must scan the entire table to process the ...
https://dev.mysql.com/doc/refman/8.4/en/atomic-ddl.html
Supported table DDL statements include CREATE, ALTER, and DROP statements for databases, tablespaces, tables, and indexes, and the TRUNCATE TABLE statement. An atomic DDL statement combines the data dictionary updates, storage engine operations, and ...The operation is either committed, with applicable changes persisted to the data dictionary, storage engine, and binary log, or is rolled back, even if the server halts during the ...
https://dev.mysql.com/doc/refman/8.4/en/prepare.html
PREPARE stmt_name FROM preparable_stmt The PREPARE statement prepares a SQL statement and assigns it a name, stmt_name, by which to refer to the statement later. The prepared statement is executed with EXECUTE and released with DEALLOCATE PREPARE.
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-metric-sysschema-statementanalysis-first-seen-category.html
Lists the Sys Schema Statement Analysis by First Time Seen metrics and provides a brief description of each. Table 6.38 Sys Schema Statement Analysis by First Time Seen Metrics NameDescriptionAvg Latency The average wait time per timed occurrence ...Tmp Tables To Disk Pct The percentage of internal in-memory temporary tables that were converted to on-disk ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-metric-sysschema-statementanalysis-total-executions-category.html
Lists the Sys Schema Statement Analysis by Total Executions metrics and provides a brief description of each. Table 6.39 Sys Schema Statement Analysis by Total Executions Metrics NameDescriptionAvg Latency The average wait time per timed occurrence ...Tmp Tables To Disk Pct The percentage of internal in-memory temporary tables that were converted to on-disk ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-metric-sysschema-statementanalysis-total-latency-category.html
Lists the Sys Schema Statement Analysis by Total Latency metrics and provides a brief description of each. Table 6.40 Sys Schema Statement Analysis by Total Latency Metrics NameDescriptionAvg Latency The average wait time per timed occurrence of ...
https://dev.mysql.com/doc/c-api/8.4/en/c-api-multiple-queries.html
By default, mysql_real_query() and mysql_query() interpret their statement string argument as a single statement to be executed, and you process the result according to whether the statement produces a result set (a set of rows, as for SELECT) or ...This capability is enabled by special options that are specified either when you connect to the server with mysql_real_connect() or after connecting by calling ...
https://dev.mysql.com/doc/refman/8.4/en/signal.html
To retrieve information from the diagnostics area, use the GET DIAGNOSTICS statement (see Section 15.6.7.3, “GET DIAGNOSTICS Statement”). SIGNAL Overview Signal Condition Information Items Effect of Signals on Handlers, Cursors, and Statements ...SIGNAL provides error information to a handler, to an outer portion of the application, or to the ...
https://dev.mysql.com/doc/refman/8.4/en/lock-tables.html
Another use for UNLOCK TABLES is to release the global read lock acquired with the FLUSH TABLES WITH READ LOCK statement, which enables you to lock all tables in all databases. Table Lock Acquisition Table Lock Release Interaction of Table Locking ... LOCK {TABLE | TABLES} tbl_name [[AS] alias] lock_type [, tbl_name [[AS] alias] lock_type] ...