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https://dev.mysql.com/doc/refman/8.4/en/innodb-transaction-isolation-levels.html
Gap locking is only used for foreign-key constraint checking and duplicate-key checking. Transaction isolation is one of the foundations of database processing. Isolation is the I in the acronym ACID; the isolation level is the setting that ...
https://dev.mysql.com/doc/refman/8.4/en/keywords.html
Certain keywords, such as SELECT, DELETE, or BIGINT, are reserved and require special treatment for use as identifiers such as table and column names. This may also be true for the names of built-in functions. Some keywords which are otherwise ...
https://dev.mysql.com/doc/refman/8.4/en/load-data.html
Index Handling To ignore foreign key constraints during the load operation, execute a SET foreign_key_checks = 0 statement before executing LOAD DATA. The file can be read from the server host or the client host, depending on whether the LOCAL ...
https://dev.mysql.com/doc/refman/8.4/en/lock-tables.html
If you lock a table explicitly with LOCK TABLES, any tables related by a foreign key constraint are opened and locked implicitly. LOCK {TABLE | TABLES} tbl_name [[AS] alias] lock_type [, tbl_name [[AS] alias] lock_type] ... lock_type: { READ ...
https://dev.mysql.com/doc/refman/8.4/en/memory-storage-engine.html
This does not enable the table to grow beyond the max_heap_table_size value, which still acts as a constraint on maximum table size. The MEMORY storage engine (formerly known as HEAP) creates special-purpose tables with contents that are stored in ...
https://dev.mysql.com/doc/refman/8.4/en/merge-table-problems.html
A MERGE table cannot maintain uniqueness constraints over the entire table. The following are known problems with MERGE tables: MERGE child tables are locked through the parent table. If the parent is a temporary table, it is not locked, and thus ...
https://dev.mysql.com/doc/refman/8.4/en/metadata-locking.html
Metadata locks are extended, as necessary, to tables related by a foreign key constraint to prevent conflicting DML and DDL operations from executing concurrently on the related tables. MySQL uses metadata locking to manage concurrent access to ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-repair.html
The discussion in this section describes how to use myisamchk on MyISAM tables (extensions .MYI and .MYD). You can also use the CHECK TABLE and REPAIR TABLE statements to check and repair MyISAM tables. See Section 15.7.3.2, “CHECK TABLE ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-storage-engine.html
MyISAM is based on the older (and no longer available) ISAM storage engine but has many useful extensions. Table 18.2 MyISAM Storage Engine Features Feature Support B-tree indexes Yes Backup/point-in-time recovery (Implemented in the server, rather ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-disk-data-objects.html
This is also true for dropping these objects, subject to the following constraints: A log file group cannot be dropped as long as any tablespaces use it. NDB Cluster Disk Data storage is implemented using the following objects: Tablespace: Acts as ...