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https://dev.mysql.com/partitioning-selection.html
Explicit selection of partitions and subpartitions for rows matching a given WHERE condition is supported. Partition selection is similar to partition pruning, in that only specific partitions are checked for matches, but differs in two key ...
https://dev.mysql.com/partitioning-types.html
This section discusses the types of partitioning which are available in MySQL 8.0. This type of partitioning assigns rows to partitions based on column values falling within a given range. For information about an extension to this type, RANGE ...
https://dev.mysql.com/mysql-cluster-programs-ndb-desc.html
ndb_desc provides a detailed description of one or more NDB tables. Usage ndb_desc -c connection_string tbl_name -d db_name [options] ndb_desc -c connection_string index_name -d db_name -t tbl_name Additional options that can be used with ndb_desc ...
https://dev.mysql.com/myisamchk-table-info.html
varchar prefix 0 1024 87 80 varchar 0 3 168 3 multip. uint24 NULL 0 1024 Field Start Length Nullpos Nullbit Type 1 1 1 2 2 4 no zeros 3 6 81 varchar 4 87 81 varchar 5 168 3 1 1 no zeros 6 171 3 1 2 no zeros Explanations for the types of information ... To obtain a description of a MyISAM table or statistics about it, use the commands shown ...
https://dev.mysql.com/create-index.html
However, prefix lengths for index specifications in CREATE TABLE, ALTER TABLE, and CREATE INDEX statements are interpreted as number of characters for nonbinary string types (CHAR, VARCHAR, TEXT) and number of bytes for binary string types (BINARY, ... CREATE [UNIQUE | FULLTEXT | SPATIAL] INDEX index_name [index_type] ON tbl_name (key_part,...) [index_option] [algorithm_option | lock_option] ...
https://dev.mysql.com/creating-tables.html
Use a CREATE TABLE statement to specify the layout of your table: mysql> CREATE TABLE pet (name VARCHAR(20), owner VARCHAR(20), species VARCHAR(20), sex CHAR(1), birth DATE, death DATE); VARCHAR is a good choice for the name, owner, and species ...
https://dev.mysql.com/innodb-compression-internals.html
The compression of B-tree nodes (of both clustered and secondary indexes) is handled differently from compression of overflow pages used to store long VARCHAR, BLOB, or TEXT columns, as explained in the following sections. Compressing BLOB, VARCHAR, ... This section describes some internal implementation details about compression for InnoDB ...
https://dev.mysql.com/charset-unicode-conversion.html
In terms of table structure, these are the primary potential incompatibilities: For the variable-length character data types (VARCHAR and the TEXT types), the maximum permitted length in characters is less for utf8mb4 columns than for utf8mb3 ...
https://dev.mysql.com/partitioning-handling-nulls.html
Partitioning in MySQL does nothing to disallow NULL as the value of a partitioning expression, whether it is a column value or the value of a user-supplied expression. Even though it is permitted to use NULL as the value of an expression that must ...
https://dev.mysql.com/innodb-row-format.html
Tables that use the REDUNDANT row format store the first 768 bytes of variable-length column values (VARCHAR, VARBINARY, and BLOB and TEXT types) in the index record within the B-tree node, with the remainder stored on overflow pages. Tables that ...
Document created the 26/06/2006, last modified the 26/10/2018
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