if exists(
SELECT
1
FROM
sys.tables t
INNER
JOIN
sys.columns c
ON
t.object_id = c.object_id
INNER
JOIN
sys.default_constraints dc
ON
c.default_object_id = dc.object_id
WHERE
t.
name
=
'你的表名稱'
AND
c.
name
=
'你的列名稱'
)
存在默認值約束的處理
else
不存在默認值約束的處理