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https://dev.mysql.com/doc/refman/8.4/en/symbolic-links-to-tables.html
For InnoDB tables, use the alternative technique explained in Section 17.6.1.2, “Creating Tables Externally” instead. To instruct a running MySQL server to perform the symlinking, use the DATA DIRECTORY and INDEX DIRECTORY options to CREATE ...
https://dev.mysql.com/doc/refman/8.4/en/federated-create.html
To create a FEDERATED table you should follow these steps: Create the table on the remote server. Alternatively, make a note of the table definition of an existing table, perhaps using the SHOW CREATE TABLE statement. Create the table on the local ...Note You can improve the performance of a FEDERATED table by adding indexes to the table on the ...The optimization occurs because the query sent to the remote server ...
https://dev.mysql.com/doc/refman/8.4/en/extensions-to-ansi.html
The KEY_BLOCK_SIZE clause in the following comment is executed only by servers from MySQL 5.1.10 or higher: CREATE TABLE t1(a INT, KEY (a)) /*!50110 KEY_BLOCK_SIZE=1024 */; The following descriptions list MySQL extensions, organized by category. Be ... MySQL Server supports some extensions that you are not likely to find in other SQL ...
https://dev.mysql.com/doc/refman/8.4/en/sys-table-exists.html
Tests whether a given table exists as a regular table, a TEMPORARY table, or a view. If both a temporary and a permanent table exist with the given name, TEMPORARY is returned. Parameters in_db VARCHAR(64): The name of the database in which to ...
https://dev.mysql.com/doc/refman/8.4/en/checksum-table.html
This row-by-row calculation is what you get with the EXTENDED clause, with InnoDB and all other storage engines other than MyISAM, and with MyISAM tables not created with the CHECKSUM=1 clause. For MyISAM tables created with the CHECKSUM=1 clause, ...[QUICK | EXTENDED] CHECKSUM TABLE reports a checksum for the contents of a ...You can use this statement to verify that the contents are the same before and after a backup, ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-deadlock-example.html
Client A enables innodb_print_all_deadlocks, creates two tables, 'Animals' and 'Birds', and inserts data into each. The following example illustrates how an error can occur when a lock request causes a deadlock. Thererfore, the previous read-only ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-pruning.html
By limiting the search, it is possible to expend much less time and effort in finding matching rows than by scanning all partitions in the table. When the optimizer can make use of partition pruning in performing this query, execution of the query ... The optimization known as partition pruning is based on a relatively simple concept which can be described as “Do not scan partitions where there can be no matching ...
https://dev.mysql.com/doc/internals/en/optimizer-partition-pruning.html
Suppose that we have a partitioned table with N columns, using partitioning type p_type and the partitioning function p_func, represented like this: CREATE TABLE t (columns) PARTITION BY p_type(p_func(col1, col2,... 7.3.2.1.2.2 Interval Walking Let ...With non-transactional tables such as MyISAM, locks are placed on entire partitioned ...Partitions that did not get into this set (that is, those that ...
https://dev.mysql.com/doc/refman/8.4/en/fulltext-stopwords.html
The following example demonstrates creating and configuring a new global stopword table for InnoDB. To see the default InnoDB stopword list, query the Information Schema INNODB_FT_DEFAULT_STOPWORD table. The stopword table must have a single VARCHAR ... The stopword list is loaded and searched for full-text queries using the server character set and collation (the values of the character_set_server and collation_server system ...
https://dev.mysql.com/doc/ndbapi/en/ndb-start-mysql-data-types.html
These and later versions of the MySQL Server and NDB Cluster use the new temporal types by default, can read and write data using the old temporal types, but cannot create tables that use the old types. This section provides information about the ...The MySQL TINYINT, SMALLINT, INT, and BIGINT data types map to NDB types having the same names and storage requirements as their MySQL ...