SQL - 检查列是否自动递增

Question

我正在尝试运行查询以检查列是否自动递增.我可以检查类型,默认值,它是否可以为空等等,但我无法弄清楚如何自动递增测试.这是我如何测试其他东西:

SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'my_table'
AND COLUMN_NAME = 'my_column'
AND DATA_TYPE = 'int'
AND COLUMN_DEFAULT IS NULL
AND IS_NULLABLE = 'NO'
--AND AUTO_INCREMENTS = 'YES'

不幸的是,没有AUTO_INCREMENTS可比较的列.那么如何测试列自动递增？

Answer 1

对于MySql,请检入EXTRA列:

SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'my_table'
    AND COLUMN_NAME = 'my_column'
    AND DATA_TYPE = 'int'
    AND COLUMN_DEFAULT IS NULL
    AND IS_NULLABLE = 'NO'
    AND EXTRA like '%auto_increment%'

对于Sql Server,使用sys.columns和is_identity列:

SELECT 
    is_identity
FROM sys.columns
WHERE 
    object_id = object_id('my_table')
    AND name = 'my_column'

Answer 2

假设MySQL,该EXTRA列将指示它是否是AUTO_INCREMENT.

| TABLE_CATALOG | TABLE_SCHEMA | ... |          EXTRA | ... |
-------------------------------------------------------------
|           def |   db_2_00314 | ... | auto_increment | ... |

对于MSSQL,请看这里.