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https://dev.mysql.com/doc/refman/8.4/en/information-schema-tables-table.html
The information_schema_stats_expiry system variable defines the period of time before cached table statistics expire. If there are no cached statistics or statistics have expired, statistics are retrieved from storage engines when querying table ...
https://dev.mysql.com/doc/ndbapi/en/ndb-table.html
This section provides information about the Table class, which models a database table in the NDB API. It is possible using the NDB API to create tables independently of the MySQL server. However, it is usually not advisable to do so, since tables ...This class extends the Object class, which in turn is an inner class of the NdbDictionary ...
https://dev.mysql.com/doc/refman/8.4/en/lock-tables.html
LOCK {TABLE | TABLES} tbl_name [[AS] alias] lock_type [, tbl_name [[AS] alias] lock_type] ... lock_type: { READ [LOCAL] | WRITE } UNLOCK {TABLE | TABLES} MySQL enables client sessions to acquire table locks explicitly for the purpose of cooperating ...One session cannot acquire locks for another session or release locks held by another ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-table-wait-summary-tables.html
The following sections describe the table I/O and lock wait summary tables: table_io_waits_summary_by_index_usage: Table I/O waits per index table_io_waits_summary_by_table: Table I/O waits per table table_lock_waits_summary_by_table: Table lock ...
https://dev.mysql.com/doc/refman/8.4/en/create-table.html
(Some valid select or union statement) CREATE TABLE creates a table with the given name. By default, tables are created in the default database, using the InnoDB storage engine. An error occurs if the table exists, if there is no default database, ...| {FULLTEXT | SPATIAL} [INDEX | KEY] [index_name] (key_part,...) [index_option] ...
https://dev.mysql.com/doc/refman/8.4/en/alter-table.html
ALTER TABLE tbl_name [alter_option [, alter_option] ...] [partition_options] alter_option: { table_options | ADD [COLUMN] col_name column_definition [FIRST | AFTER col_name] | ADD [COLUMN] (col_name column_definition,...) | ADD {INDEX | KEY} ...| ...
https://dev.mysql.com/doc/mysql-errors/8.4/en/server-error-reference.html
Error number: 1005; Symbol: ER_CANT_CREATE_TABLE; SQLSTATE: HY000 Message: Can't create table '%s' (errno: %d - %s) InnoDB reports this error when a table cannot be created. If the error message refers to error 150, table creation failed because a ... The MySQL server writes some error messages to its error log, and sends others to client ...
https://dev.mysql.com/doc/refman/8.4/en/monitor-alter-table-performance-schema.html
You can monitor ALTER TABLE progress for InnoDB tables using Performance Schema. There are seven stage events that represent different phases of ALTER TABLE. Each stage event reports a running total of WORK_COMPLETED and WORK_ESTIMATED for the ...
https://dev.mysql.com/doc/refman/8.4/en/glossary.html
If related data is being updated across multiple tables, queries see either all old values or all new values, not a mix of old and new values. adaptive flushing An algorithm for InnoDB tables that smooths out the I/O overhead introduced by ... These ...
https://dev.mysql.com/doc/refman/8.4/en/derived-table-optimization.html
The optimizer handles derived tables, view references, and common table expressions the same way: It avoids unnecessary materialization whenever possible, which enables pushing down conditions from the outer query to derived tables and produces more ...The outer query does not specify DISTINCT, HAVING, or ORDER ...