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/control-flow-functions.html
If all types are character string (CHAR or VARCHAR), the result is VARCHAR with maximum length determined by the longest character length of the operands. SET and ENUM are treated similar to VARCHAR; the result is VARCHAR. The second syntax returns ...
https://dev.mysql.com/explain-output.html
In this context, VARCHAR and CHAR are considered the same if they are declared as the same size. To fix this disparity between column lengths, use ALTER TABLE to lengthen ActualPC from 10 characters to 15 characters: mysql> ALTER TABLE tt MODIFY ...
https://dev.mysql.com/myisam-storage-engine.html
MyISAM also supports the following features: Support for a true VARCHAR type; a VARCHAR column starts with a length stored in one or two bytes. Tables with VARCHAR columns may have fixed or dynamic row length. The sum of the lengths of the VARCHAR ... MyISAM is based on the older (and no longer available) ISAM storage engine but has many useful ...
https://dev.mysql.com/partitioning-limitations.html
This section discusses current restrictions and limitations on MySQL partitioning support. The following constructs are not permitted in partitioning expressions: Stored procedures, stored functions, UDFs, or plugins. For a list of SQL functions ...
https://dev.mysql.com/blob.html
Similarly, you can regard a TEXT column as a VARCHAR column. BLOB and TEXT differ from VARBINARY and VARCHAR in the following ways: For indexes on BLOB and TEXT columns, you must specify an index prefix length. MySQL Connector/ODBC defines BLOB ...
https://dev.mysql.com/charset-column.html
Every “character” column (that is, a column of type CHAR, VARCHAR, a TEXT type, or any synonym) has a column character set and a column collation. CREATE TABLE t1 ( col1 CHAR(10) CHARACTER SET utf8 COLLATE utf8_unicode_ci ) CHARACTER SET latin1 ...
https://dev.mysql.com/fulltext-stopwords.html
The stopword table must have a single VARCHAR column named value. 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/glossary.html
off-page column A column containing variable-length data (such as BLOB and VARCHAR) that is too long to fit on a B-tree page. overflow page Separately allocated disk pages that hold variable-length columns (such as BLOB and VARCHAR) that are too ...
https://dev.mysql.com/if.html
[ELSE statement_list] END IF The IF statement for stored programs implements a basic conditional construct. Note There is also an IF() function, which differs from the IF statement described here. The IF statement can have THEN, ELSE, and ELSEIF ...
