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https://dev.mysql.com/doc/refman/9.7/en/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 utf8mb4 COLLATE utf8mb4_unicode_ci ) CHARACTER SET ...
https://dev.mysql.com/doc/refman/9.7/en/create-table-foreign-keys.html
Consequently, BLOB and TEXT columns cannot be included in a foreign key because indexes on those columns must always include a prefix length. For NDB tables, ON DELETE CASCADE is not supported where the child table contains one or more columns of ...
https://dev.mysql.com/doc/refman/9.7/en/csv-storage-engine.html
The CSV storage engine stores data in text files using comma-separated values format. When you create a CSV table, the server creates a plain text data file having a name that begins with the table name and has a .CSV extension. The CSV storage ...
https://dev.mysql.com/doc/refman/9.7/en/descending-indexes.html
For InnoDB full-text search, this means that the index required on the FTS_DOC_ID column of the indexed table cannot be defined as a descending index. Explicitly specified ASC and DESC designators for HASH, FULLTEXT, and SPATIAL indexes results in ... MySQL supports descending indexes: DESC in an index definition is no longer ignored but causes storage of key values in descending ...
MySQL 9.7 Reference Manual :: A.11 MySQL 9.7 FAQ: MySQL Chinese, Japanese, and Korean Character Sets
https://dev.mysql.com/doc/refman/9.7/en/faqs-cjk.html
Why do some LIKE and FULLTEXT searches with CJK characters fail? A.11.12. Sometimes adding or changing a <meta> tag suffices to correct the problem: for example, to insure that the user agent interprets page content as UTF-8, include <meta ... This ...
https://dev.mysql.com/doc/refman/9.7/en/faqs-innodb-change-buffer.html
What types of operations modify secondary indexes and result in change buffering? A.16.2. How much space does InnoDB use for the change buffer? A.16.5. How do I determine the current size of the change buffer? A.16.6. Where can I find additional ...
https://dev.mysql.com/doc/refman/9.7/en/features.html
Data Types Many data types: signed/unsigned integers 1, 2, 3, 4, and 8 bytes long, FLOAT, DOUBLE, CHAR, VARCHAR, BINARY, VARBINARY, TEXT, BLOB, DATE, TIME, DATETIME, TIMESTAMP, YEAR, SET, ENUM, and OpenGIS spatial types. An index may use a prefix of ... This section describes some of the important characteristics of the MySQL Database ...
https://dev.mysql.com/doc/refman/9.7/en/firewall-component.html
See Section 6.5.1.2, “mysql Client Commands”, and Section 6.5.1.5, “Executing SQL Statements from a Text File”, for more information about using the source command. For more information, see Section 6.5.1.2, “mysql Client Commands”, as ... Purpose: Provide an application-level firewall enabling the database administrator to allow or block SQL statements based on matching them against accepted statement ...
https://dev.mysql.com/doc/refman/9.7/en/generated-column-index-optimizations.html
For example: CREATE TABLE t1 (f1 INT, gc INT AS (f1 + 1) STORED, INDEX (gc)); The generated column, gc, is defined as the expression f1 + 1. The column is also indexed and the optimizer can take that index into account during execution plan ...
https://dev.mysql.com/doc/refman/9.7/en/gis-wkt-functions.html
These functions take as arguments a Well-Known Text (WKT) representation and, optionally, a spatial reference system identifier (SRID). For a description of WKT format, see Well-Known Text (WKT) Format. ST_GeomFromText() accepts a WKT value of any ...Functions in this section detect arguments in either Cartesian or geographic spatial reference systems (SRSs), and return results appropriate to the ...