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https://dev.mysql.com/create-table.html
Character data types (CHAR, VARCHAR, the TEXT types, ENUM, SET, and any synonyms) synonyms) can include CHARACTER SET to specify the character set for the column. For CHAR, VARCHAR, BINARY, and VARBINARY columns, indexes can be created that use only ... CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name (create_definition,...) [table_options] [partition_options] CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name [(create_definition,...)] [table_options] [partition_options] [IGNORE | REPLACE] [AS] query_expression CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name { LIKE old_tbl_name | (LIKE old_tbl_name) } create_definition: col_name column_definition | {INDEX|KEY} [index_name] [index_type] (key_part,...) [index_option] ...
https://dev.mysql.com/load-xml.html
Suppose that we have a table named person, created as shown here: USE test; CREATE TABLE person ( person_id INT NOT NULL PRIMARY KEY, fname VARCHAR(40) NULL, lname VARCHAR(40) NULL, created TIMESTAMP ); Suppose further that this table is initially ...The tagname in the optional ROWS IDENTIFIED BY clause must also be given as a literal string, and must be surrounded by angle brackets (< and ...
https://dev.mysql.com/storage-requirements.html
To calculate the number of bytes used to store a particular CHAR, VARCHAR, or TEXT column value, you must take into account the character set used for that column and whether the value contains multibyte characters. VARCHAR, VARBINARY, and the BLOB ... InnoDB Table Storage Requirements NDB Table Storage Requirements Numeric Type Storage Requirements Date and Time Type Storage Requirements String Type Storage Requirements Spatial Type Storage Requirements JSON Storage Requirements The storage requirements for table data on disk depend on several ...
https://dev.mysql.com/innodb-restrictions.html
For example, you might hit this limit with a column prefix index of more than 191 characters on a TEXT or VARCHAR column, assuming a utf8mb4 character set and the maximum of 4 bytes for each character. ERROR 1070 (42000): Too many key parts ...
https://dev.mysql.com/alter-table.html
For example, changing VARCHAR(20) to VARCHAR(30) is permitted, but changing it to VARCHAR(1024) is not because that alters the number of length bytes required to store individual values. Changing the Character Set To change the table default ...
https://dev.mysql.com/mysql-cluster-programs-ndb-restore.html
--fields-optionally-enclosed-by Property Value Command-Line Format --fields-optionally-enclosed-by Type String Default Value The string passed to this option is used to enclose column values containing character data (such as CHAR, VARCHAR, BINARY, ... The NDB Cluster restoration program is implemented as a separate command-line utility ndb_restore, which can normally be found in the MySQL bin ...
https://dev.mysql.com/innodb-fulltext-index.html
FULLTEXT indexes are created on text-based columns (CHAR, VARCHAR, or TEXT columns) to help speed up queries and DML operations on data contained within those columns, omitting any words that are defined as stopwords. mysql> CREATE TABLE ...A ...
https://dev.mysql.com/innodb-memcached-porting-mysql.html
Too-long values in a string column such as a VARCHAR are truncated by removing some characters, which could produce nonsensical numeric values. Consider these aspects of memcached applications when adapting an existing MySQL schema or application ...
https://dev.mysql.com/json-table-functions.html
This section contains information about JSON functions that convert JSON data to tabular data. JSON_TABLE(expr, path COLUMNS (column_list) [AS] alias) Extracts data from a JSON document and returns it as a relational table having the specified ...
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 ...
Document created the 26/06/2006, last modified the 26/10/2018
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