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https://dev.mysql.com/doc/refman/8.4/en/concurrent-inserts.html
If the variable is set to ALWAYS (or 2), concurrent inserts at the end of the table are permitted even for tables that have deleted rows. This is done to ensure that you can re-create an exact copy of your tables by applying the log during a backup ...If there are multiple INSERT statements, they are queued and performed in sequence, concurrently with the SELECT ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-limits.html
This section describes limits for InnoDB tables, indexes, tablespaces, and other aspects of the InnoDB storage engine. The index key prefix length limit is 3072 bytes for InnoDB tables that use DYNAMIC or COMPRESSED row format. The index key prefix ...For example, you might hit this limit with a column prefix index of more than 191 characters on a TEXT or VARCHAR column, assuming a utf8mb4 character set and the maximum of 4 bytes for each ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-single-multi.html
Before the introduction of online DDL, it was common practice to combine many DDL operations into a single ALTER TABLE statement. Because each ALTER TABLE statement involved copying and rebuilding the table, it was more efficient to make several ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-undo-logs.html
Rollback segments reside in undo tablespaces and in the global temporary tablespace. Undo logs that reside in the global temporary tablespace are used for transactions that modify data in user-defined temporary tables. Each undo tablespace and the ... An undo log is a collection of undo log records associated with a single read-write ...
https://dev.mysql.com/doc/refman/8.4/en/myisamchk-general-options.html
The options described in this section can be used for any type of table maintenance operation performed by myisamchk. The sections following this one describe options that pertain only to specific operations, such as table checking or repairing.
https://dev.mysql.com/doc/refman/8.4/en/mysqlbinlog-row-events.html
# at 218 #080828 15:03:08 server id 1 end_log_pos 258 Write_rows: table id 17 flags: STMT_END_F BINLOG ' fAS3SBMBAAAALAAAANoAAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ= fAS3SBcBAAAAKAAAAAIBAAAQABEAAAAAAAEAA//8AQAAAAVhcHBsZQ== '/*!*/; ... # at 302 ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-hash.html
To partition a table using HASH partitioning, it is necessary to append to the CREATE TABLE statement a PARTITION BY HASH (expr) clause, where expr is an expression that returns an integer. In addition, you most likely want to follow this with ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-subpartitions.html
Subpartitioning—also known as composite partitioning—is the further division of each partition in a partitioned table. Consider the following CREATE TABLE statement: CREATE TABLE ts (id INT, purchased DATE) PARTITION BY RANGE( YEAR(purchased) ) ...Each of these partitions—p0, p1, and p2—is further divided into 2 ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-restrictions.html
If you save event information in another table, you should not assume that the original events remain available later. For example, if you select events from a performance_schema table into a temporary table, intending to join that table with the ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-thread-filtering.html
The threads table contains a row for each server thread. For the Performance Schema to monitor a thread, these things must be true: The thread_instrumentation consumer in the setup_consumers table must be YES. Monitoring occurs only for those ...