Sql服务器 - 递归删除

Question

我试图删除用户数据及其位于不同表中的所有相关数据。 所有的表都有外键，但没有级联删除。

我调查了一些选项：

1. 开启所有FK级联删除，删除，删除级联删除。
2. 从下往上删除UP，循环所有的叶子删除并重复此操作直到Root。

有没有更多的智能选项或其他技术？

我正在使用Microsoft SQL Server 2012（SP1）

Answer 1

Oracle解决方案：

How to generate DELETE statements in PL/SQL, based on the tables FK relations?

SQL Server解决方案：

Generate Delete Statement From Foreign Key Relationships in SQL 2008?

希望它可以帮助

Answer 2

这些是最好和最有效的。对于生产查询，我会使用2。

我能想到的会（IMO）只适用于在测试环境中快速和肮脏的清除数据的唯一其他方式（避免需要分析正确的顺序）

1. 禁用所有FKS删除所需数据然后重新启用FK。这是效率低下的，因为它们需要重新启用以避免将FK置于不可信状态，这意味着所有保存的数据都需要重新验证。
2. 按照任意顺序列出受影响表上的所有DELETE语句，并根据需要多次运行该批次，直到成功完成且没有FK错误。

Answer 3

我相信这是可能做到

DELETE FROM tbl1 
INNER JOIN tbl2 
ON tbl1.ID = tbl2.tbl1ID 
WHERE 
tbl1.somthing = x 

Answer 4

级联删除是容易的，性能良好的，可靠的。适用于多个层面。查询计划很有趣，看起来很好。

如果您希望手动删除，请确保每个表只出现一个查询以提高效率。您可以在删除语句中使用连接来加入父级别以过滤要删除的行。

Answer 5

我发现它一个很好的解决方案， 下：How to generate DELETE statements in PL/SQL, based on the tables FK relations?

生成功能：

IF OBJECT_ID('dbo.udfGetFullQualName') IS NOT NULL 
    DROP FUNCTION dbo.udfGetFullQualName; 

GO 
CREATE FUNCTION dbo.udfGetFullQualName 
(@ObjectId INT) 
RETURNS VARCHAR (300) 
AS 
BEGIN 
    DECLARE @schema_id AS BIGINT; 
    SELECT @schema_id = schema_id 
    FROM sys.tables 
    WHERE object_id = @ObjectId; 
    RETURN '[' + SCHEMA_NAME(@schema_id) + '].[' + OBJECT_NAME(@ObjectId) + ']'; 
END 

GO 
--============ Supporting Function dbo.udfGetOnJoinClause 
IF OBJECT_ID('dbo.udfGetOnJoinClause') IS NOT NULL 
    DROP FUNCTION dbo.udfGetOnJoinClause; 

GO 
CREATE FUNCTION dbo.udfGetOnJoinClause 
(@fkNameId INT) 
RETURNS VARCHAR (1000) 
AS 
BEGIN 
    DECLARE @OnClauseTemplate AS VARCHAR (1000); 
    SET @OnClauseTemplate = '[<@pTable>].[<@pCol>] = [<@cTable>].[<@cCol>] AND '; 
    DECLARE @str AS VARCHAR (1000); 
    SET @str = ''; 
    SELECT @str = @str + REPLACE(REPLACE(REPLACE(REPLACE(@OnClauseTemplate, '<@pTable>', OBJECT_NAME(rkeyid)), '<@pCol>', COL_NAME(rkeyid, rkey)), '<@cTable>', OBJECT_NAME(fkeyid)), '<@cCol>', COL_NAME(fkeyid, fkey)) 
    FROM dbo.sysforeignkeys AS fk 
    WHERE fk.constid = @fkNameId; --OBJECT_ID('FK_ProductArrearsMe_ProductArrears') 
    RETURN LEFT(@str, LEN(@str) - LEN(' AND ')); 
END 

GO 
--=========== CASECADE DELETE STORED PROCEDURE dbo.uspCascadeDelete 
IF OBJECT_ID('dbo.uspCascadeDelete') IS NOT NULL 
    DROP PROCEDURE dbo.uspCascadeDelete; 

GO 
CREATE PROCEDURE dbo.uspCascadeDelete 
@ParentTableId VARCHAR (300), @WhereClause VARCHAR (2000), @ExecuteDelete CHAR (1)='N', --'N' IF YOU NEED DELETE SCRIPT 
@FromClause VARCHAR (8000)='', @Level INT=0 -- TABLE NAME OR OBJECT (TABLE) ID (Production.Location) WHERE CLAUSE (Location.LocationID = 7) 'Y' IF WANT TO DELETE DIRECTLY FROM SP, IF LEVEL 0, THEN KEEP DEFAULT 
AS -- writen by Daniel Crowther 16 Dec 2004 - handles composite primary keys 
SET NOCOUNT ON; 
/* Set up debug */ 
DECLARE @DebugMsg AS VARCHAR (4000), 
@DebugIndent AS VARCHAR (50); 
SET @DebugIndent = REPLICATE('---', @@NESTLEVEL) + '> '; 
IF ISNUMERIC(@ParentTableId) = 0 
    BEGIN -- assume owner is dbo and calculate id 
     IF CHARINDEX('.', @ParentTableId) = 0 
      SET @ParentTableId = OBJECT_ID('[dbo].[' + @ParentTableId + ']'); 
     ELSE 
      SET @ParentTableId = OBJECT_ID(@ParentTableId); 
    END 
IF @Level = 0 
    BEGIN 
     PRINT @DebugIndent + ' **************************************************************************'; 
     PRINT @DebugIndent + ' *** Cascade delete ALL data from ' + dbo.udfGetFullQualName(@ParentTableId); 
     IF @ExecuteDelete = 'Y' 
      PRINT @DebugIndent + ' *** @ExecuteDelete = Y *** deleting data...'; 
     ELSE 
      PRINT @DebugIndent + ' *** Cut and paste output into another window and execute ***'; 
    END 
DECLARE @CRLF AS CHAR (2); 
SET @CRLF = CHAR(13) + CHAR(10); 
DECLARE @strSQL AS VARCHAR (4000); 
IF @Level = 0 
    SET @strSQL = 'SET NOCOUNT ON' + @CRLF; 
ELSE 
    SET @strSQL = ''; 
SET @strSQL = @strSQL + 'PRINT ''' + @DebugIndent + dbo.udfGetFullQualName(@ParentTableId) + ' Level=' + CAST (@@NESTLEVEL AS VARCHAR) + ''''; 
IF @ExecuteDelete = 'Y' 
    EXECUTE (@strSQL); 
ELSE 
    PRINT @strSQL; 
DECLARE curs_children CURSOR LOCAL FORWARD_ONLY 
    FOR SELECT DISTINCT constid AS fkNameId, -- constraint name 
         fkeyid AS cTableId 
     FROM dbo.sysforeignkeys AS fk 
     WHERE fk.rkeyid <> fk.fkeyid -- WE DO NOT HANDLE self referencing tables!!! 
       AND fk.rkeyid = @ParentTableId; 
OPEN curs_children; 
DECLARE @fkNameId AS INT, 
@cTableId AS INT, 
@cColId AS INT, 
@pTableId AS INT, 
@pColId AS INT; 
FETCH NEXT FROM curs_children INTO @fkNameId, @cTableId; --, @cColId, @pTableId, @pColId 
DECLARE @strFromClause AS VARCHAR (1000); 
DECLARE @nLevel AS INT; 
IF @Level = 0 
    BEGIN 
     SET @FromClause = 'FROM ' + dbo.udfGetFullQualName(@ParentTableId); 
    END 
WHILE @@FETCH_STATUS = 0 
    BEGIN 
     SELECT @strFromClause = @FromClause + @CRLF + '  INNER JOIN ' + dbo.udfGetFullQualName(@cTableId) + @CRLF + '  ON ' + dbo.udfGetOnJoinClause(@fkNameId); 
     SET @nLevel = @Level + 1; 
     EXECUTE dbo.uspCascadeDelete @ParentTableId = @cTableId, @WhereClause = @WhereClause, @ExecuteDelete = @ExecuteDelete, @FromClause = @strFromClause, @Level = @nLevel; 
     SET @strSQL = 'DELETE FROM ' + dbo.udfGetFullQualName(@cTableId) + @CRLF + @strFromClause + @CRLF + 'WHERE ' + @WhereClause + @CRLF; 
     SET @strSQL = @strSQL + 'PRINT ''---' + @DebugIndent + 'DELETE FROM ' + dbo.udfGetFullQualName(@cTableId) + '  Rows Deleted: '' + CAST(@@ROWCOUNT AS VARCHAR)' + @CRLF + @CRLF; 
     IF @ExecuteDelete = 'Y' 
      EXECUTE (@strSQL); 
     ELSE 
      PRINT @strSQL; 
     FETCH NEXT FROM curs_children INTO @fkNameId, @cTableId; 
    --, @cColId, @pTableId, @pColId 
    END 
IF @Level = 0 
    BEGIN 
     SET @strSQL = @CRLF + 'PRINT ''' + @DebugIndent + dbo.udfGetFullQualName(@ParentTableId) + ' Level=' + CAST (@@NESTLEVEL AS VARCHAR) + ' TOP LEVEL PARENT TABLE''' + @CRLF; 
     SET @strSQL = @strSQL + 'DELETE FROM ' + dbo.udfGetFullQualName(@ParentTableId) + ' WHERE ' + @WhereClause + @CRLF; 
     SET @strSQL = @strSQL + 'PRINT ''' + @DebugIndent + 'DELETE FROM ' + dbo.udfGetFullQualName(@ParentTableId) + ' Rows Deleted: '' + CAST(@@ROWCOUNT AS VARCHAR)' + @CRLF; 
     IF @ExecuteDelete = 'Y' 
      EXECUTE (@strSQL); 
     ELSE 
      PRINT @strSQL; 
    END 
CLOSE curs_children; 
DEALLOCATE curs_children; 

用法：

EXEC uspCascadeDelete 
@ParentTableId = '[VAULT].[Package]', 
@WhereClause = 'CreatedBy =''VZBMNSTEST'''