我开发了WPF客户端，该客户端使用Azure SQL数据库查询货运发票。
客户一直抱怨货件清单的加载时间长，我发现对于每个货件，应用程序都会查询Azure SQL数据库以获取货件发票，这需要时间。
查询是在每个货件的foreach循环中进行的，没有其他方法可以执行，因为货件是通过在客户端中进行过滤从Web服务加载的。 发票表中没有使用过滤器的列。
因此要进行测试，我做了以下工作：
创建了一个TSQL脚本，该脚本对100批货物运行Dynamic sql以获取发票，并在SQL Server Management Studio中执行该发票。 对每100批货物执行动态SQL。 我记录了动态sql执行之前和之后的时间 每批货物的动态sql exeutionExecutiontime为0毫秒，足够快。
在C＃中创建了一个控制台应用程序，该应用程序从Azure收集了100个货件 将它们存储在列表中，然后运行查询以在列表上的foreachloop中获取发票。每批货物的执行时间在43到58毫秒之间变化，这很长。
为了进行基准测试，我在网络中我们自己的SQL服务器之一上创建了Invoice表，从Azure SQLdatabase复制了数据并运行了控制台应用程序。 每批货物的执行时间在0到15毫秒之间变化，这足够快。
所以我的问题是，在Microsoft SQLServer Management Studio VS控制台应用程序中，在循环中运行100个查询之间会有如此巨大的区别吗？ MSSMS是否具有魔术连接？
样本代码：
//Console application
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlClient;
using System.Data;
using System.IO;
namespace ConsoleApp8
{
class Program
{
public struct res
{
public string ShipmentId;
public DateTime St;
public DateTime Sl;
public double Exectimems;
public res(string shipmentid, DateTime st)
{
ShipmentId = shipmentid;
St = st;
Sl = new DateTime();
Exectimems = 0;
}
}
static void Main(string[] args)
{
//string connstr = "Data Source=LocalNetWorkSQLServer;Initial Catalog=Dummy;User ID=sa;Password=somepassword;MultipleActiveResultSets=True";
string connstr = "Server = tcp:Server.database.windows.net;Database=Dummy;User ID =Username@Server;Password=somepassword;Trusted_Connection=False;Encrypt=True;MultipleActiveResultSets=True;";
List<string> Shipments = new List<string>();
List<res> results = new List<res>();
SqlConnectionStringBuilder scb = new SqlConnectionStringBuilder(connstr);
//Get all shipments to find invoices on and put them in a list.
string sql = "Select top 100 ShipmentId"
+ " From("
+ " Select distinct shipmentid"
+ " From TKL_Invoices With(readuncommitted)"
+ " Where OfficeId = 'swe') x";
using (SqlConnection cnn = new SqlConnection(connstr))
{
cnn.Open();
using (SqlCommand cmd = new SqlCommand(sql, cnn))
{
cmd.CommandType = System.Data.CommandType.Text;
SqlDataReader rd = cmd.ExecuteReader();
while (rd.Read())
{
Shipments.Add(rd["ShipmentId"].ToString());
}
}
cnn.Close();
}
//Get first invoice on each shipment
sql = "TKL_GetSavedInvoices";
using (SqlConnection cnn = new SqlConnection(connstr))
{
cnn.Open();
foreach (string Shipment in Shipments)
{
res r = new res(Shipment, DateTime.Now);
using (SqlCommand cmd = new SqlCommand(sql, cnn))
{
cmd.CommandType = System.Data.CommandType.StoredProcedure;
cmd.CommandType = System.Data.CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("@ShipmentId", Shipment);
cmd.Parameters.AddWithValue("@OfficeId", "swe");
cmd.Parameters.AddWithValue("@Dbg", "1");
string invoice = cmd.ExecuteScalar().ToString();
r.Sl = DateTime.Now;
TimeSpan timeDiff = r.St - r.Sl;
r.Exectimems = timeDiff.TotalMilliseconds;
results.Add(r);
Console.WriteLine(Shipment, r.Exectimems.ToString());
}
}
cnn.Close();
}
//Log result to file
string prefix = "NetWorkSQLServer";
if (scb.DataSource.ToLower().Contains("tcp:"))
prefix = "Azure";
string filename = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "WPF_Client_" + prefix + "_QueryResult_" + scb.DataSource.Replace(':','_') + "." + scb.InitialCatalog + ".csv");
if (File.Exists(filename))
File.Delete(filename);
StringBuilder sb = new StringBuilder();
sb.Append("ShipmentId;TimeBeforeQyery;TimeAfterQyery;QueryTimeMilliseconds");
foreach (res r in results)
{
sb.Append(Environment.NewLine)
.Append(r.ShipmentId).Append(";")
.Append(r.St.ToLongTimeString()).Append(";")
.Append(r.Sl.ToLongTimeString()).Append(";")
.Append(r.Exectimems.ToString()).Append(";");
}
File.WriteAllText(filename, sb.ToString());
Console.WriteLine("Done");
Console.ReadKey();
}
}
}
SQL数据库表：
/****** Object: Index [ix_TKL_Invoices001] Script Date: 2018-06-21 15:12:43 ******/
DROP INDEX [ix_TKL_Invoices001] ON [dbo].[Tkl_Invoices]
GO
/****** Object: Table [dbo].[Tkl_Invoices] Script Date: 2018-06-21 15:12:43 ******/
DROP TABLE [dbo].[Tkl_Invoices]
GO
/****** Object: Table [dbo].[Tkl_Invoices] Script Date: 2018-06-21 15:12:43 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Tkl_Invoices](
[ShipmentId] [varchar](50) NOT NULL,
[OfficeId] [varchar](50) NULL,
[InvoiceNo] [varchar](50) NOT NULL,
CONSTRAINT [PK_Tkl_Invoices] PRIMARY KEY CLUSTERED
(
[ShipmentId] ASC,
[InvoiceNo] 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
SET ANSI_PADDING ON
GO
/****** Object: Index [ix_TKL_Invoices001] Script Date: 2018-06-21 15:12:43 ******/
CREATE NONCLUSTERED INDEX [ix_TKL_Invoices001] ON [dbo].[Tkl_Invoices]
(
[OfficeId] ASC,
[ShipmentId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
--Data for the table
Insert into Tkl_Invoices(ShipmentId, OfficeId, InvoiceNo)
Select '1511546743', 'SWE', '250279'
Union Select '1512550199', 'SWE', '1111111'
Union Select '1512554318', 'SWE', '250249'
Union Select '1601561108', 'SWE', '250279'
Union Select '1602561957', 'SWE', '249700'
Union Select '1602562876', 'SWE', '250582'
Union Select '1602566412', 'SWE', '250577'
Union Select '1602567219', 'SWE', '249699'
Union Select '1602567387', 'SWE', '250577'
Union Select '1603568831', 'SWE', '250577'
Union Select '1603569044', 'SWE', '250326'
Union Select '1603569143', 'SWE', '249846'
Union Select '1603569720', 'SWE', '249994'
Union Select '1603570257', 'SWE', '250279'
Union Select '1603570259', 'SWE', '250582'
Union Select '1603570940', 'SWE', '1234'
Union Select '1603572374', 'SWE', '250118'
Union Select '1603572376', 'SWE', '250200'
Union Select '1603572378', 'SWE', '250034'
Union Select '1603572450', 'SWE', '249923'
Union Select '1603572450', 'SWE', '250262'
Union Select '1603572601', 'SWE', '249927'
Union Select '1603572603', 'SWE', '250577'
Union Select '1603573496', 'SWE', '249701'
Union Select '1603573826', 'SWE', '249712'
Union Select '1603574012', 'SWE', '250577'
Union Select '1603574022', 'SWE', '250055'
Union Select '1603574184', 'SWE', '249888'
Union Select '1603574193', 'SWE', '249702'
Union Select '1603574195', 'SWE', '250239'
Union Select '1603574417', 'SWE', '249921'
Union Select '1603574610', 'SWE', '1000000'
Union Select '1603574652', 'SWE', '249704'
Union Select '1603574865', 'SWE', '249706'
Union Select '1603574874', 'SWE', '250109'
Union Select '1603575030', 'SWE', '250175'
Union Select '1603575032', 'SWE', '250172'
Union Select '1603575127', 'SWE', '249732'
Union Select '1603575147', 'SWE', '250155'
Union Select '1603575181', 'SWE', '250108'
Union Select '1603575531', 'SWE', '250034'
Union Select '1603575538', 'SWE', '249994'
Union Select '1603575540', 'SWE', '250168'
Union Select '1603575558', 'SWE', '250084'
Union Select '1603575562', 'SWE', '250234'
Union Select '1603575566', 'SWE', '250057'
Union Select '1603575586', 'SWE', '250034'
Union Select '1603575592', 'SWE', '250193'
Union Select '1603575594', 'SWE', '250185'
Union Select '1603575598', 'SWE', '250034'
Union Select '1603575627', 'SWE', '250080'
Union Select '1603575633', 'SWE', '250163'
Union Select '1603575635', 'SWE', '249820'
Union Select '1603575637', 'SWE', '250108'
Union Select '1603575641', 'SWE', '250034'
Union Select '1603575644', 'SWE', '250102'
Union Select '1603575646', 'SWE', '250084'
Union Select '1603575653', 'SWE', '250117'
Union Select '1603575655', 'SWE', '250117'
Union Select '1603575868', 'SWE', '250084'
Union Select '1603575872', 'SWE', '250171'
Union Select '1603575874', 'SWE', '250036'
Union Select '1603575876', 'SWE', '250036'
Union Select '1603575879', 'SWE', '250036'
Union Select '1603575881', 'SWE', '250036'
Union Select '1603575887', 'SWE', '250036'
Union Select '1603575894', 'SWE', '250081'
Union Select '1603575896', 'SWE', '250065'
Union Select '1603575905', 'SWE', '250160'
Union Select '1603575909', 'SWE', '250083'
Union Select '1603575914', 'SWE', '250186'
Union Select '1603575917', 'SWE', '250105'
Union Select '1603575919', 'SWE', '250094'
Union Select '1603575921', 'SWE', '250183'
Union Select '1603575966', 'SWE', '250104'
Union Select '1603575976', 'SWE', '250124'
Union Select '1603575984', 'SWE', '250199'
Union Select '1603575992', 'SWE', '250501'
Union Select '1603575998', 'SWE', '250170'
Union Select '1603576000', 'SWE', '250034'
Union Select '1603576183', 'SWE', '250095'
Union Select '1603576188', 'SWE', '250114'
Union Select '1603576192', 'SWE', '250159'
Union Select '1603576209', 'SWE', '250129'
Union Select '1603576268', 'SWE', '250176'
Union Select '1603576286', 'SWE', '250130'
Union Select '1603576294', 'SWE', '249715'
Union Select '1603576296', 'SWE', '249716'
Union Select '1604576489', 'SWE', '250135'
Union Select '1604576823', 'SWE', '250036'
Union Select '1604576884', 'SWE', '250039'
Union Select '1604576909', 'SWE', '250145'
Union Select '1604576913', 'SWE', '249922'
Union Select '1604576944', 'SWE', '249682'
Union Select '1604577069', 'SWE', '249717'
Union Select '1604577112', 'SWE', '250082'
Union Select '1604577121', 'SWE', '250234'
Union Select '1604577133', 'SWE', '250234'
Union Select '1604577137', 'SWE', '250234'
Union Select '1604577139', 'SWE', '250234'
--SQL Stored procedure to get invoices(@Dbg is to get one invoice only)
/****** Object: StoredProcedure [dbo].[TKL_GetSavedInvoices] Script Date: 2018-06-21 15:23:51 ******/
DROP PROCEDURE [dbo].[TKL_GetSavedInvoices]
GO
/****** Object: StoredProcedure [dbo].[TKL_GetSavedInvoices] Script Date: 2018-06-21 15:23:51 ******/
SET ANSI_NULLS OFF
GO
SET QUOTED_IDENTIFIER OFF
GO
CREATE procedure [dbo].[TKL_GetSavedInvoices]
@ShipmentId nvarchar(50)
,@OfficeId nvarchar(255) = null
,@Dbg smallint = 0
as
begin
declare @InvoiceNo nvarchar(50)
if Exists(Select 1 From TKL_Invoices with(readuncommitted)
where ShipmentId = @ShipmentId
and OfficeId = isnull(@OfficeId, OfficeId)
)
begin
If(@dbg = 0)
begin
select
InvoiceNo
from TKL_Invoices with(readuncommitted)
where ShipmentId = @ShipmentId
and OfficeId = isnull(@OfficeId, OfficeId)
order by Head desc
OPTION ( OPTIMIZE FOR UNKNOWN )
End Else
begin
select
@InvoiceNo = InvoiceNo
from TKL_Invoices with(readuncommitted)
where ShipmentId = @ShipmentId
and OfficeId = isnull(@OfficeId, OfficeId)
order by Head desc
OPTION ( OPTIMIZE FOR UNKNOWN )
Select @InvoiceNo as InvoiceNo
End
End Else
begin
Select 'NA' as InvoiceNo
End
end
GO
答案 0 :(得分：0)
这很浪费！
foreach (string Shipment in Shipments)
{
res r = new res(Shipment, DateTime.Now);
using (SqlCommand cmd = new SqlCommand(sql, cnn))
{
cmd.CommandType = System.Data.CommandType.StoredProcedure;
cmd.CommandType = System.Data.CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("@ShipmentId", Shipment);
cmd.Parameters.AddWithValue("@OfficeId", "swe");
cmd.Parameters.AddWithValue("@Dbg", "1");
为什么在每个循环上都要花一个新命令而不是坚持执行该命令？
public static void SQLLoop()
{
List<string> shipments = new List<string>();
string sql = "adsffo;hkjasd";
using (SqlConnection cnn = new SqlConnection("asfd"))
{
cnn.Open();
using (SqlCommand cmd = new SqlCommand(sql, cnn))
{
cmd.CommandType = System.Data.CommandType.StoredProcedure;
List<res> results = new List<res>();
cmd.CommandType = System.Data.CommandType.StoredProcedure;;
cmd.Parameters.Add("@ShipmentId", SqlDbType.VarChar, 100);
cmd.Parameters.AddWithValue("@OfficeId", "swe");
cmd.Parameters.AddWithValue("@Dbg", "1");
foreach (string shipment in shipments)
{
res r = new res(shipment, DateTime.Now);
cmd.Parameters["@ShipmentId"].Value = shipment;
string invoice = cmd.ExecuteScalar().ToString();
r.Sl = DateTime.Now;
TimeSpan timeDiff = r.St - r.Sl;
r.Exectimems = timeDiff.TotalMilliseconds;
results.Add(r);
Console.WriteLine(shipment, r.Exectimems.ToString());
}
}
}
}