获取表的primary key

SELECT cu.Column_Name
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS t 
	LEFT JOIN INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE cu ON t.CONSTRAINT_NAME = cu.CONSTRAINT_NAME AND cu.TABLE_NAME = t.TABLE_NAME
	LEFT JOIN INFORMATION_SCHEMA.COLUMNS c ON c.COLUMN_NAME = cu.COLUMN_NAME AND c.TABLE_NAME = cu.TABLE_NAME
WHERE Constraint_Type = 'PRIMARY KEY ' AND cu.Table_Name = '<table name>'
ORDER BY c.ORDINAL_POSITION