如何在不知道其表的情况下删除约束？

Question

我想删除 SQL Server 数据库中的每个用户对象，但保留表及其记录不变。但我也想放弃它的限制。所以我创建了这个查询来获取我将粘贴到 SMSS 中并在之后执行的丢弃声明：

SELECT
    'DROP ' +
    CASE 
        WHEN [sys].[all_objects].type IN ('AF','FN','FS','FT','IF','TF') THEN 'FUNCTION '
        WHEN [sys].[all_objects].type IN ('D','C','F','PK','UQ') THEN 'CONSTRAINT '
        WHEN [sys].[all_objects].type IN ('IT','S','U') THEN 'TABLE '
        WHEN [sys].[all_objects].type IN ('P','PC','RF','X') THEN 'PROCEDURE '
        WHEN [sys].[all_objects].type IN ('TA','TR') THEN 'TRIGGER '
        WHEN [sys].[all_objects].type = 'R' THEN 'RULE '
        WHEN [sys].[all_objects].type = 'SN' THEN 'SYNONYM '
        WHEN [sys].[all_objects].type = 'TT' THEN 'TYPE '
        WHEN [sys].[all_objects].type = 'V' THEN 'VIEW '
    END +
    SCHEMA_NAME(sys.[all_objects].[schema_id]) + '.' + OBJECT_NAME(object_id) + '; ', OBJECT_NAME(object_id), [sys].[all_objects].[type_desc], [sys].[all_objects].[type], SCHEMA_NAME(sys.[all_objects].[schema_id])
FROM 
    sys.[all_objects] WITH (NOLOCK) -- WHERE (OBJECT_DEFINITION(object_id) LIKE '%' + @toDrop + '%') AND ([sys].[all_objects].[name] <> @toDrop);
WHERE
    (SCHEMA_NAME(sys.[all_objects].[schema_id]) <> 'sys') AND
    (SCHEMA_NAME(sys.[all_objects].[schema_id]) <> 'INFORMATION_SCHEMA') AND
    ([sys].[all_objects].[type_desc] <> 'USER_TABLE')
ORDER BY
    [sys].[all_objects].[type_desc], SCHEMA_NAME(sys.[all_objects].[schema_id]), OBJECT_NAME(object_id)

问题是，在约束情况下我必须使用ALTER TABLE x DROP CONSTRAINT y

那么如何轻松消除所有约束呢？

Answer 1

    SELECT
        'ALTER TABLE ' + 
        SCHEMA_NAME(sys.[objects].[schema_id]) + '.' + OBJECT_NAME([sys].[objects].[parent_object_id]) +
        ' DROP CONSTRAINT ' +
        OBJECT_NAME(object_id) + '; ', OBJECT_NAME(object_id), [sys].[objects].[type_desc], [sys].[objects].[type], SCHEMA_NAME(sys.[objects].[schema_id]),
        OBJECT_NAME([sys].[objects].[parent_object_id])
    FROM 
        sys.[objects] WITH (NOLOCK) 
    WHERE
        (SCHEMA_NAME(sys.[objects].[schema_id]) <> 'sys') AND
        ([sys].[objects].[type_desc] <> 'USER_TABLE') AND
        ([sys].[objects].TYPE IN ('D','C','F','PK','UQ')) AND
    ORDER BY
        [sys].[objects].[type_desc], SCHEMA_NAME(sys.[objects].[schema_id]), OBJECT_NAME(object_id)
GO