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https://dev.mysql.com/doc/refman/8.4/en/cache-index.html
The key cache referred to in a CACHE INDEX statement can be created by setting its size with a parameter setting statement or in the server parameter settings. A key cache must exist before you assign indexes to it, or an error occurs: mysql> CACHE ...| tbl_name PARTITION (partition_list) } IN key_cache_name tbl_index_list: tbl_name [{INDEX|KEY} (index_name[, index_name] ...)] partition_list: { partition_name[, partition_name] ...
https://dev.mysql.com/doc/refman/8.4/en/charset-database.html
The CREATE DATABASE and ALTER DATABASE statements have optional clauses for specifying the database character set and collation: CREATE DATABASE db_name [[DEFAULT] CHARACTER SET charset_name] [[DEFAULT] COLLATE collation_name] ALTER DATABASE db_name ... Every database has a database character set and a database ...
https://dev.mysql.com/doc/refman/8.4/en/charset-unicode-utf16.html
The utf16 character set is the ucs2 character set with an extension that enables encoding of supplementary characters: For a BMP character, utf16 and ucs2 have identical storage characteristics: same code values, same encoding, same length. For a ...
https://dev.mysql.com/doc/refman/8.4/en/faqs-triggers.html
How are triggers managed in MySQL? Triggers can be created using the CREATE TRIGGER statement, and dropped using DROP TRIGGER. See Section 15.1.22, “CREATE TRIGGER Statement”, and Section 15.1.34, “DROP TRIGGER Statement”, for more about ...
https://dev.mysql.com/doc/refman/8.4/en/file-permissions.html
For example, mysqld might issue the following error message when you create a table: ERROR: Can't find file: 'path/with/file_name' (Errcode: 13) The default UMASK and UMASK_DIR values are 0640 and 0750, respectively. If this is unsuitable, create ...
https://dev.mysql.com/doc/refman/8.4/en/fulltext-search.html
Full-text indexes can be used only with InnoDB or MyISAM tables, and can be created only for CHAR, VARCHAR, or TEXT columns. A FULLTEXT index definition can be given in the CREATE TABLE statement when a table is created, or added later using ALTER ... MATCH (col1,col2,...) AGAINST (expr [search_modifier]) search_modifier: { IN NATURAL LANGUAGE MODE | IN NATURAL LANGUAGE MODE WITH QUERY EXPANSION | IN BOOLEAN MODE | WITH QUERY EXPANSION } MySQL has support for full-text indexing and searching: A full-text index in MySQL is an index of type ...
https://dev.mysql.com/doc/refman/8.4/en/getting-information.html
Extra displays special information about columns: If a column was created with the AUTO_INCREMENT option, the value is auto_increment rather than empty. You can obtain the CREATE TABLE statement necessary to create an existing table using the SHOW ... What if you forget the name of a database or table, or what the structure of a given table is (for example, what its columns are called)? MySQL addresses this problem through several statements that provide information about the databases and tables it ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-responses-failure-expel.html
You can use the group_replication_member_expel_timeout system variable to allow additional time between the creation of a suspicion and the expulsion of the suspect member. A suspicion is created when one server does not receive messages from ...A ...
https://dev.mysql.com/doc/refman/8.4/en/hash-joins.html
If this happens, you should be aware that the join may not succeed if a hash join cannot fit into memory and it creates more files than set for open_files_limit. It is possible to control whether hash joins are employed using one of the BNL and ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-partitions-table.html
PARTITION_EXPRESSION The expression for the partitioning function used in the CREATE TABLE or ALTER TABLE statement that created the table's current partitioning scheme. For each such row: The SUBPARTITION_NAME, SUBPARTITION_ORDINAL_POSITION, ...