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https://dev.mysql.com/doc/refman/5.7/en/create-table-generated-columns.html
Values of a generated column are computed from an expression included in the column definition. Generated columns are supported by the NDB storage engine beginning with MySQL NDB Cluster 7.5.3. Generated column definitions have this syntax: col_name ...The VIRTUAL or STORED keyword indicates how column values are stored, which has implications for column use: VIRTUAL: Column values are not stored, but are evaluated when rows are read, immediately after any BEFORE ...
https://dev.mysql.com/doc/refman/5.7/en/alter-table-generated-columns.html
ALTER TABLE operations permitted for generated columns are ADD, MODIFY, and CHANGE. CREATE TABLE t1 (c1 INT); ALTER TABLE t1 ADD COLUMN c2 INT GENERATED ALWAYS AS (c1 + 1) STORED; The data type and expression of generated columns can be modified.
https://dev.mysql.com/doc/refman/5.7/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. This occurs if the WHERE, ORDER BY, or GROUP BY clause refers to an expression that matches the definition ...The column is also indexed and the optimizer can take that index into account during execution plan ...You can ...
https://dev.mysql.com/doc/refman/5.7/en/mysqlslap.html
--auto-generate-sql-add-autoincrement Command-Line Format --auto-generate-sql-add-autoincrement Type Boolean Default Value FALSE Add an AUTO_INCREMENT column to automatically generated tables. --number-char-cols=N, -x N Command-Line Format ...
https://dev.mysql.com/doc/refman/5.7/en/glossary.html
The values from such a column can be used as lookup keys in various contexts, and because they are auto-generated there is no reason to ever change them; for this reason, primary key columns are often specified as auto-incrementing. base column A ...
https://dev.mysql.com/doc/refman/5.7/en/create-table-secondary-indexes.html
A secondary index may be created on one or more virtual columns or on a combination of virtual columns and regular columns or stored generated columns. When a secondary index is created on a virtual generated column, generated column values are ...A ...The data length of logged values is limited by the index key limit of 767 bytes for COMPACT and REDUNDANT row formats, and 3072 bytes for DYNAMIC and COMPRESSED row ...
https://dev.mysql.com/doc/refman/5.7/en/password-hashing.html
A 4.1 or later server generates long hashes only if certain conditions are met: The Password column must be wide enough to hold long values and old_passwords must not be set to 1. If the column has not been updated and still has the pre-4.1 width of ...The client can do this by using the PASSWORD() function to generate a password hash, or by using a password-generating statement (CREATE USER, GRANT, or SET ... Note The ...
https://dev.mysql.com/doc/refman/5.7/en/information-schema-columns-table.html
GENERATION_EXPRESSION For generated columns, displays the expression used to compute column values. For information about generated columns, see Section 13.1.18.7, “CREATE TABLE and Generated Columns”. The COLUMNS table has these columns: ...
https://dev.mysql.com/doc/refman/5.7/en/show-columns.html
SHOW [FULL] {COLUMNS | FIELDS} {FROM | IN} tbl_name [{FROM | IN} db_name] [LIKE 'pattern' | WHERE expr] SHOW COLUMNS displays information about the columns in a given table. SHOW COLUMNS displays information only for those columns for which you ...
https://dev.mysql.com/doc/refman/5.7/en/innodb-auto-increment-handling.html
Once a value is generated for an auto-increment column, it cannot be rolled back, whether or not the “INSERT-like” statement is completed, and whether or not the containing transaction is rolled back. Specifying NULL or 0 for the AUTO_INCREMENT ... InnoDB provides a configurable locking mechanism that can significantly improve scalability and performance of SQL statements that add rows to tables with AUTO_INCREMENT ...