use*_*364 2 sql-server stored-procedures sql-server-2008 sql-server-performance
我有一个名为 Transaction_tbl 的表,其中包含超过 400 000 条记录。这是表结构:
CREATE TABLE [dbo].[Transaction_tbl](
[transactID] [numeric](18, 0) IDENTITY(1,1) NOT NULL,
[TBarcode] [varchar](20) NULL,
[cmpid] [int] NULL,
[Locid] [int] NULL,
[PSID] [int] NULL,
[PCID] [int] NULL,
[PCdID] [int] NULL,
[PlateNo] [varchar](20) NULL,
[vtid] [int] NULL,
[Compl] [bit] NULL,
[self] [bit] NULL,
[LstTic] [bit] NULL,
[Gticket] [int] NULL,
[Cticket] [int] NULL,
[Ecode] [varchar](50) NULL,
[dtime] [datetime] NULL,
[LICID] [int] NULL,
[PAICID] [int] NULL,
[Plot] [varchar](50) NULL,
[mkid] [int] NULL,
[mdlid] [int] NULL,
[Colid] [int] NULL,
[Comments] [varchar](100) NULL,
[Kticket] [int] NULL,
[PAmount] [numeric](18, 2) NULL,
[Payid] [int] NULL,
[Paid] [bit] NULL,
[Paydate] [datetime] NULL,
[POICID] [int] NULL,
[DelDate] [datetime] NULL,
[DelEcode] [nvarchar](50) NULL,
[PAICdate] [datetime] NULL,
[KeyRoomDate] [datetime] NULL,
[Status] [int] NULL,
CONSTRAINT [PK_Transaction_tbl] PRIMARY KEY CLUSTERED
(
[transactID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
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我在 Locid, dtime 列上有一个非聚集索引。我有一个像这样的存储过程:
ALTER procedure [dbo].[IBS_fetchreleasedinpodiumgridnew]
@locid INTEGER = NULL
AS BEGIN
SET NOCOUNT ON
DECLARE @TodayMinus7Days DATETIME
Declare @krrt integer
Declare @DT integer
SET @TodayMinus7Days = getdate()-1
SELECT
t.TBarcode, t.PlateNo, t.DelEcode,cast(t.Paydate as Time) [REQ],
datediff(MINUTE, t.PayDate,
CASE t.Status
WHEN 3 THEN GETDATE()
WHEN 4 THEN t.KeyRoomDate
When 5 THEN t.KeyRoomDate
End) as KRRT,
datediff(MINUTE,t.PayDate,
CASE t.Status
WHEN 3 THEN GETDATE()
WHEN 4 THEN GETDATE()
WHEN 5 THEN t.DelDate
END) as DT
FROM
dbo.Transaction_tbl t
WHERE
(
([status] IN (3,4))
OR
([status] = 5 AND DATEDIFF(n, DelDate, GETDATE()) <= 3)
)
AND locid = 6 AND dtime >= @TodayMinus7Days
ORDER BY
paydate
end
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我的执行计划是这样的:

但大多数时候这需要很长时间才能执行..在这种情况下我如何提高存储过程的执行性能?
我想使用的任何其他方法..任何帮助都非常有用。谢谢
查询执行计划显示排序需要很长时间..所以如果我给paydate查询性能提供索引会增加吗?相反,dtime >= @TodayMinus7Days我给出了这样的代码:
dtime >= OPTION (optimize for (@TodayMinus7Days))
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但出现错误:关键字“OPTION”附近的语法不正确。
除了优化查询之外,我还可以立即建议采取一些措施来提高存储过程的性能。
参数嗅探:当存储过程传递参数时,它会分析数据集以找出最有效的索引。这很有用,尽管计划被缓存,并且会过时,导致存储过程在低效的执行计划上运行。
解决方案:重新声明参数或针对未知参数值优化存储过程
抑制行计数:为了提高存储过程的性能,您可以做的最简单的事情之一就是 SET NOCOUNT ON。这将防止 SQL Server 在执行每个语句后将消息发送回客户端,而存储过程不需要这样做。这看起来是一个很小的改进,但结果是显而易见的。
解决方案:设置 NOCOUNT ON
下面的代码片段提供了它们在存储过程中的位置的示例。请注意,如果您重新声明参数,则无需针对未知进行优化,反之亦然。
CREATE PROCEDURE dbo.example_proc
(
@USER_PARAM VARCHAR(200)
)
AS
BEGIN
-- suppress the number of rows returned
SET NOCOUNT ON;
-- Re-declaring the variable will prevent paramater sniffing
DECLARE @LOCAL_USER_PARAM VARCHAR(200) = @USER_PARAM
SELECT
*
FROM some_table st
WHERE st.some_column = @LOCAL_USER_PARAM
-- If you don't re-declare params, you can add this line
OPTION (OPTIMIZE FOR (@USER_PARAM UNKNOWN))
--
END
GO
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