Question

我正在寻找删除所有表内容的更好方法。当前，我们的过程如下图所示。不幸的是，它似乎有不同的问题，例如强制序列化，函数联接...。在每个测试在4个不同的数据库上并行执行测试之后，会花费很多时间。有没有更好的方法（更快，更好的性能）？即使对当前查询进行优化也没问题。

  	IF (OBJECT_ID('delete_tables') IS NOT NULL)
	DROP PROCEDURE delete_tables
GO

CREATE PROCEDURE delete_tables AS
BEGIN
	DECLARE @table_name VARCHAR(255);
	DECLARE @tablenames TABLE (table_name VARCHAR(255));
	DECLARE @tablenamestmp TABLE (table_name VARCHAR(255));
	DECLARE @text NVARCHAR(MAX);
	
	INSERT INTO @tablenames 
        SELECT st.name 
        FROM sys.tables st
		INNER JOIN sys.schemas ss ON st.schema_id = ss.schema_id
		INNER JOIN sys.partitions sp ON sp.object_id = st.object_id
		WHERE st.is_ms_shipped = 0 
          AND ss.name = 'dbo' 
          AND sp.index_id IN (1,0)
		  AND st.name NOT LIKE 'comm_specialtable_%'
		GROUP BY st.name 
        HAVING SUM(sp.rows) > 0

	INSERT INTO @tablenamestmp 
        SELECT * FROM @tablenames;

	WHILE EXISTS (SELECT 1 FROM @tablenamestmp)
	BEGIN
		SELECT TOP 1 @table_name = table_name 
        FROM @tablenamestmp;

		IF @table_name IS NOT NULL
		BEGIN

			SET @text = 'ALTER TABLE '+ @table_name+ ' NOCHECK CONSTRAINT ALL'
			EXEC sp_executesql @text;

		END
		DELETE FROM @tablenamestmp WHERE table_name = @table_name;
	END

	INSERT INTO @tablenamestmp SELECT * FROM @tablenames;

	WHILE exists(SELECT 1 FROM @tablenamestmp)
	BEGIN
		SELECT TOP 1 @table_name = table_name FROM @tablenamestmp;
		IF @table_name IS NOT NULL
		BEGIN

			SET @text = 'SET QUOTED_IDENTIFIER ON; DELETE FROM '+ @table_name
			EXEC sp_executesql @text;

			SET @text = 'ALTER TABLE '+ @table_name+ ' WITH CHECK CHECK CONSTRAINT all'
			EXEC sp_executesql @text;

		END
		DELETE FROM @tablenamestmp WHERE table_name = @table_name;
	END


end

Answer 1

您可以使用TRUNCATE TABLE代替注释中提到的DELETE FROM来避免日志记录-但是，为什么要首先这样做呢？如果使用的是EF，则使用内存数据库；如果使用的是SQL的最新版本，则使用数据库快照；或者删除数据库并发布新的空白数据库；或者拥有初始状态的备份并将其恢复到顶部，则将使用可能都是更好的方法。

SQL Server：删除所有表中的数据->是否有性能更好的查询？

1 个答案: