Per MySql, controlla il EXTRA
colonna:
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%'
Per SQL Server, usa sys.columns
e is_identity
colonna:
SELECT
is_identity
FROM sys.columns
WHERE
object_id = object_id('my_table')
AND name = 'my_column'