Question

有没有办法优化我的查询？当我添加这个参数时，我的存储过程会增加6秒来输出我的结果。

SET @primary_name  =    
            ISNULL(
                STUFF((SELECT 
                        'Convert(nvarchar(4000),' + column_name + ')+'',,''+'
                        FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
                        WHERE 
                            OBJECTPROPERTY(OBJECT_ID(constraint_name), 'IsPrimaryKey') = 1
                            AND QUOTENAME(table_schema) + '.' + QUOTENAME(table_name) = @table_name 
                        FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)')
                ,1,0,'')
            ,'ISNULL')

SET @primary_name = (LEFT(@primary_name,LEN(@primary_name) -6 ))

IF @primary_name = ''
BEGIN
SET @primary_name = ''''''
END

Answer 1

您可以尝试删除ISNULL并在第二次SET操作中执行吗？

Answer 2

刚刚执行的代码减少了6秒@TavoloPerUno

SELECT @primary_name  = (SELECT top 1 QUOTENAME(keys.COLUMN_NAME) FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE keys
                            WHERE keys.TABLE_NAME =PARSENAME(@table_name, 1)
                              and keys.TABLE_SCHEMA = PARSENAME(@table_name, 2)
                            and OBJECTPROPERTY(OBJECT_ID(constraint_name), 'IsPrimaryKey') = 1)

优化获取主键的查询

2 个答案: