https://dev.mysql.com/partitioning-pruning.html
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 values”. By limiting the search, it is possible to expend much less time and ...
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/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/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/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/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 ...
https://dev.mysql.com/local-variable-scope.html
The scope of a local variable is the BEGIN ... The variable can be referred to in blocks nested within the declaring block, except those blocks that declare a variable with the same name. Because local variables are in scope only during stored ...
