sql-server - 将 FOREIGN KEY 约束从一个数据库复制到另一个数据库

Question

我有一个具有 FOREIGN KEY 约束的本地数据库。

该网站数据库的实时版本没有任何这些外键约束。

如何“复制/粘贴”，仅将外键约束从一个数据库导入/导出到另一个数据库？

我不想复制任何数据，只复制约束。

谢谢

Answer 1

您可以使用我在http://www.siusic.com/wphchen/how-to-script-out-all-the-foreign-keys-of-a-table-106.html找到的这个脚本。将 tablename1 和 tablename2 替换为您希望为其获取外键的表列表。

select  'ALTER TABLE '+object_name(a.parent_object_id)+
    ' ADD CONSTRAINT '+ a.name +
    ' FOREIGN KEY (' + c.name + ') REFERENCES ' +
    object_name(b.referenced_object_id) +
    ' (' + d.name + ')'
from    sys.foreign_keys a
        join sys.foreign_key_columns b
                  on a.object_id=b.constraint_object_id
        join sys.columns c
                  on b.parent_column_id = c.column_id
             and a.parent_object_id=c.object_id
        join sys.columns d
                  on b.referenced_column_id = d.column_id
            and a.referenced_object_id = d.object_id
where   object_name(b.referenced_object_id) in
    ('tablename1','tablename2')
order by c.name

Answer 2

我需要做类似的事情，我需要在多个服务器上使用相同的外键，除了已经添加了一些外键。所以我在创建语句的开头添加了一个“IF NOT EXISTS”检查：

SELECT N'
IF NOT EXISTS (SELECT * FROM sys.foreign_keys 
WHERE object_id = OBJECT_ID(''' + QUOTENAME(fk.name) + ''')
   AND parent_object_id = OBJECT_ID(''' + QUOTENAME(cs.name) + '.' + QUOTENAME(ct.name)  +''')
)
BEGIN
ALTER TABLE ' 
   + QUOTENAME(cs.name) + '.' + QUOTENAME(ct.name) 
   + ' ADD CONSTRAINT ' + QUOTENAME(fk.name) 
   + ' FOREIGN KEY (' + STUFF((SELECT ',' + QUOTENAME(c.name)
   -- get all the columns in the constraint table
    FROM sys.columns AS c 
    INNER JOIN sys.foreign_key_columns AS fkc 
    ON fkc.parent_column_id = c.column_id
    AND fkc.parent_object_id = c.[object_id]
    WHERE fkc.constraint_object_id = fk.[object_id]
    ORDER BY fkc.constraint_column_id 
    FOR XML PATH(N''), TYPE).value(N'.[1]', N'nvarchar(max)'), 1, 1, N'')
  + ') REFERENCES ' + QUOTENAME(rs.name) + '.' + QUOTENAME(rt.name)
  + '(' + STUFF((SELECT ',' + QUOTENAME(c.name)
   -- get all the referenced columns
    FROM sys.columns AS c 
    INNER JOIN sys.foreign_key_columns AS fkc 
    ON fkc.referenced_column_id = c.column_id
    AND fkc.referenced_object_id = c.[object_id]
    WHERE fkc.constraint_object_id = fk.[object_id]
    ORDER BY fkc.constraint_column_id 
    FOR XML PATH(N''), TYPE).value(N'.[1]', N'nvarchar(max)'), 1, 1, N'') + ')
    END'
FROM sys.foreign_keys AS fk
INNER JOIN sys.tables AS rt -- referenced table
  ON fk.referenced_object_id = rt.[object_id]
INNER JOIN sys.schemas AS rs 
  ON rt.[schema_id] = rs.[schema_id]
INNER JOIN sys.tables AS ct -- constraint table
  ON fk.parent_object_id = ct.[object_id]
INNER JOIN sys.schemas AS cs 
  ON ct.[schema_id] = cs.[schema_id]
WHERE rt.is_ms_shipped = 0 AND ct.is_ms_shipped = 0;

如果您不想要“IF NOT EXISTS”检查（它们真的不重要），只需删除前 5 行并在“BEGIN”之前添加“SELECT N”，如下所示：

SELECT N'BEGIN
ALTER TABLE ' 
   + QUOTENAME(cs.name) + '.' + QUOTENAME(ct.name) 

——我在网上某处找到了这个查询的核心，我已经修改了一段时间。感谢他们将大部分内容放在一起......