MySQL :: MySQL 8.0 Reference Manual

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https://dev.mysql.com/doc/refman/8.0/en/numeric-type-syntax.html

For example, applications could use the LPAD() function to zero-pad numbers up to the desired width, or they could store the formatted numbers in CHAR columns. For integer data types, M indicates the minimum display width. Display width is ...

10.2.1.16 ORDER BY Optimization

https://dev.mysql.com/doc/refman/8.0/en/order-by-optimization.html

For example, if only the first 10 bytes of a CHAR(20) column are indexed, the index cannot distinguish values past the 10th byte and a filesort is needed. Separate the paths by colon characters (:) on Unix and semicolon characters (;) on Windows.

26.2.3 COLUMNS Partitioning

https://dev.mysql.com/doc/refman/8.0/en/partitioning-columns.html

The next two sections discuss COLUMNS partitioning, which are variants on RANGE and LIST partitioning. COLUMNS partitioning enables the use of multiple columns in partitioning keys. All of these columns are taken into account both for the purpose ...

26.2.4 HASH Partitioning

https://dev.mysql.com/doc/refman/8.0/en/partitioning-hash.html

Partitioning by HASH is used primarily to ensure an even distribution of data among a predetermined number of partitions. To partition a table using HASH partitioning, it is necessary to append to the CREATE TABLE statement a PARTITION BY HASH ...

26.2.4.1 LINEAR HASH Partitioning

https://dev.mysql.com/doc/refman/8.0/en/partitioning-linear-hash.html

MySQL also supports linear hashing, which differs from regular hashing in that linear hashing utilizes a linear powers-of-two algorithm whereas regular hashing employs the modulus of the hashing function's value. We call this value V; it can be ...

29.12.21.10 The user_defined_functions Table

https://dev.mysql.com/doc/refman/8.0/en/performance-schema-user-defined-functions-table.html

The value is one of int, decimal, real, char, or row. The user_defined_functions table contains a row for each loadable function registered automatically by a component or plugin, or manually by a CREATE FUNCTION statement. For information about ...

19.1.3.1 GTID Format and Storage

https://dev.mysql.com/doc/refman/8.0/en/replication-gtids-concepts.html

A GTID is represented as a pair of coordinates, separated by a colon character (:), as shown here: GTID = source_id:transaction_id The source_id identifies the originating server. A global transaction identifier (GTID) is a unique identifier ...

10.2.1.22 Row Constructor Expression Optimization

https://dev.mysql.com/doc/refman/8.0/en/row-constructor-optimization.html

Consider the following table, which has a primary key on (c1, c2, c3): CREATE TABLE t1 ( c1 INT, c2 INT, c3 INT, c4 CHAR(100), PRIMARY KEY(c1,c2,c3) ); In this query, the WHERE clause uses all columns in the index. For example, these two statements ...

15.7.7.10 SHOW CREATE TABLE Statement

https://dev.mysql.com/doc/refman/8.0/en/show-create-table.html

row *************************** Table: t Create Table: CREATE TABLE `t` ( `id` int NOT NULL AUTO_INCREMENT, `s` char(60) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci As of MySQL 8.0.16, MySQL ...

15.7.7.22 SHOW INDEX Statement

https://dev.mysql.com/doc/refman/8.0/en/show-index.html

That is, the number of indexed characters if the column is only partly indexed, NULL if the entire column is indexed. However, prefix lengths for index specifications in CREATE TABLE, ALTER TABLE, and CREATE INDEX statements are interpreted as ...

Displaying 121 to 130 of 135 total results