Database

Do you want to know more?
WDevs.com - Open Source Code Hosting, Blogs, FTP, Mail and Forums

13-Feb-05 22:45

Why not just dump the contents of the script file into a SqlCommand object and Execute the command? That way you'd get a SqlException if something goes wrong and you can use the properties on the SQL Exception object to determine what the error is and where it occurred.

Extended stored proc

SnuhEyeless13-Feb-05 14:43

SnuhEyeless

13-Feb-05 14:43

Hi,
(not sure if this is the right forum to post into)
I have an extended stored proc (C++ dll) that calls a managed DLL that calls a web service, and all is going well until the point in the managed DLL that invokes the actual webservice. At that point SQL server complains of a connection lost.

This is probably got to do with the fact that uses SQL, however the webservice is on an entirely different box, with it's own SQL server, so I'm not sure exactly what to do about it.

Has anyone come across this before or has anyone got any suggestions on how to fix it?

thanks in advance

how to speed up sqlconnection

sianatia13-Feb-05 8:04

13-Feb-05 8:04

hi,

im using databases in MsSqlservers but i have a major problem that when i connect to my database by SqlConnection the connection is too slow but when i use query analyzer to get the same date its very fast(about 20 times faster)

i wnat to know if there is a way to speed up the sqlconnection..

Colin Angus Mackay13-Feb-05 22:57

Do you want to know more?
WDevs.com - Open Source Code Hosting, Blogs, FTP, Mail and Forums

13-Feb-05 22:57

UAU wrote:
when i connect to my database by SqlConnection the connection is too slow

UAU wrote:
i use query analyzer to get the same date its very fast

I'm confused. Do you mean that the act of initially connecting is slow? Or do you mean the act of transfering data to the application is slow?

Also, you don't supply the code you are using so it is difficult to tell if there are any bottlenecks that are causing the problem because I've always had consitent results between the speed of the Query Analyser and my .NET applications.

sianatia14-Feb-05 17:20

14-Feb-05 17:20

hi,
i mean the act of transfering data to my application is slow.

i use sqldatareader in my application and my qurey is just a simple select query,telling that when i tested the connection by SqlDataAdapter the speed was as fast as query analyzer.

is it possible that using Sqldatareader makes the data transfer too slow?

thanks

Colin Angus Mackay14-Feb-05 20:33

Do you want to know more?
WDevs.com - Open Source Code Hosting, Blogs, FTP, Mail and Forums

14-Feb-05 20:33

Since an SqlDataAdapter uses an SqlDataReader internally to perform the transfer it sounds like the code you have that takes the data from the SqlDataReader and does what ever your application needs to do with the data is causing the slowness, however I don't know what that code is or what it does so I cannot help further.

sianatia15-Feb-05 17:14

15-Feb-05 17:14

hi,
here is my code(it runs on a different thread from the main thread of application)

com.CommandText = "select something";<br />
		rd=com.ExecuteReader();<br />
		if(rd.HasRows)<br />
		{<br />
		 rd.Read();<br />
		 do<br />
		 {<br />
		  //some code goes here<br />
		 }while(rd.Read());<br />
		}<br />
		rd.Close();<br />
		if(cur.Nodes.Count > 0)<br />
		{<br />
		  com.CommandText="select somthing";<br />
		  rd=com.ExecuteReader();<br />
		  rd.Read();<br />
		 //some code goes here<br />
		}<br />
		rd.Close();

i have to run these codes for several times in my application..
thanks

Colin Angus Mackay15-Feb-05 19:50

Do you want to know more?
WDevs.com - Open Source Code Hosting, Blogs, FTP, Mail and Forums

15-Feb-05 19:50

Personally, I would have written this as

rd=com.ExecuteReader();
while(rd.Read())
{
    // some code goes here
}

Rather than do all that rd.HasRows() followed by a do{}while() but I don't see how this would make it faster unless HasRows is particularly slow.

When you timed the data transfer using a SqlAdapter did you include the time to perform all the other actions where you have indicated // some code goes here?

sianatia18-Feb-05 4:34

18-Feb-05 4:34

hi,

the action on the datareader is just pick up the datas and save them but on my machine with about 2.6 GHZ i dony think the code makes it sliw,is it possible that my sql query wich has where clause makes the transactions slow?

Colin Angus Mackay18-Feb-05 4:44

Do you want to know more?
WDevs.com - Open Source Code Hosting, Blogs, FTP, Mail and Forums

18-Feb-05 4:44

UAU wrote:
is it possible that my sql query wich has where clause makes the transactions slow?

Possibly, but it does not explain that your test using a SqlDataAdapter was faster (I am assuming you performed exactly the same query). It should have been slower because using the SqlDataAdapter makes a copy of the data in memory (in the DataSet object) before you can pick up the data and save them.

What does your SQL Query do?

sianatia18-Feb-05 18:19

18-Feb-05 18:19

hi,
this is the complete source code,but to tel you the truth i didnt use the same query with my SqlDataAdapter i made a simple select query with no where clause.

com.CommandText = "select * from general where parent = @id order by menuindex desc ";<br />
				rd=com.ExecuteReader();<br />
					if(rd.HasRows)<br />
					{<br />
						rd.Read();<br />
						do<br />
						{<br />
							if(rd.GetBoolean(2))<br />
								AddSeperatorDownLoad(cur,0);<br />
							else<br />
								AddNodetoNodeDownLoad(cur,0);<br />
							SetChild(cur.Nodes[0],rd);<br />
							list.Push(cur.Nodes[0]);<br />
						}while(rd.Read());<br />
					}<br />
					rd.Close();<br />
					if(cur.Nodes.Count > 0)<br />
					{<br />
						com.CommandText="select * from popup where menuid = @id ";<br />
						if(con.State == ConnectionState.Closed)<br />
							con.Open();<br />
						rd=com.ExecuteReader();<br />
						rd.Read();<br />
						SetPopup(cur,rd);<br />
					}<br />
					rd.Close();<br />
					if(curtag.menuItem != null && curtag.menuItem.GeneralSetting.IsPage)<br />
					{<br />
						curtag.menuItem.GeneralSetting.Page=new PageSetting();<br />
						com.CommandText="SELECT     Title, KeyWord, IsGuideLine, Description "<br />
										+" FROM         Page where menuid=@id";<br />
						rd=com.ExecuteReader();<br />
						if(rd.HasRows)<br />
						{<br />
							rd.Read();<br />
							curtag.menuItem.GeneralSetting.Page.Description=(string)rd["Description"];<br />
							curtag.menuItem.GeneralSetting.Page.IsGuideLine=(bool)rd["IsGuideLine"];<br />
							curtag.menuItem.GeneralSetting.Page.KeyWords=(string)rd["KeyWord"];<br />
							curtag.menuItem.GeneralSetting.Page.Title=((string)rd["Title"]).Replace("Karmania Media ::","");<br />
							curtag.menuItem.GeneralSetting.Page.PageContent"";<br />
						}<br />
						rd.Close();<br />
					}<br />

Colin Angus Mackay19-Feb-05 0:55

Do you want to know more?
WDevs.com - Open Source Code Hosting, Blogs, FTP, Mail and Forums

19-Feb-05 0:55

Okay, here are some general tips - They may or may not improve the speed

1. Don't use SELECT * because if your data model changes on the database then your code could break if the position of columns changes. You should always send a list of the columns you need that way if there are any additional columns in the table that you don't need to don't waste time retrieving them and you always know the order the columns will arrive in.

2. If the table is large you may wish to consider indexing the columns that are referenced in the WHERE and ORDER BY clauses. However, if you do a lot of INSERTs on the table you may have to balance the needs of inserting quickly over retrieving quickly. Adding indexes slows down INSERT, UPDATE and DELETE operations because it has to modify each affected index as well as the table.

3. You can replace

if(rd.HasRows)
{
rd.Read();
do
{
    // Do stuff here
}while(rd.Read());

with

while(rd.Read())
{
    // do stuff here
}

which removes the redundant rd.HasRows call. Because the first call to rd.Read() will return false anyway if there are no rows in the result set the rd.HasRows can be removed if the check on the while is moved to the top of the loop rather than at the bottom of the loop

I hope this helps.

sianatia23-Feb-05 17:52

Connecting to SQL Server 2000 accross a Network

23-Feb-05 17:52

hi,

i found something ,when i use sqldatareader the recieved data is more than 1 MB that the real data is less than 100KB ,is it possible that when i use datareader for many transactions i have too much overhead in recieved data?

ColdWaterBlue13-Feb-05 4:14

ColdWaterBlue

13-Feb-05 4:14

I am trying to access SQL Server 2000 across a personal network. I am using the following connection string:

"Data Source=\\GUITARCHORD\LABTRACK;Initial Catalog=LabTrack Server;Integrated Security=SSPI;User ID=someone,Password=pass"

The name of the computer is GUITARCHORD, the name of the SQL Server instance is LABTRACK, and the name of the database I am trying to connect to is LABTRACK SERVER. The user id and password are the Windows Login for the computer that SQL Server is running on. SQL Server is running but I can only access it if I am working on the same computer. I am using VB.NET to try to access this server. I am getting the following error message:

"SQL Server does not exist or access denied."

I have tried every thing I could think of for a connection string, including using TCP/IP settings. Any suggestions would be extremely helpful.

------------------------
ColdWaterBlue - Rock On

Re: Connecting to SQL Server 2000 accross a Network

Colin Angus Mackay13-Feb-05 5:22

Do you want to know more?
WDevs.com - Open Source Code Hosting, Blogs, FTP, Mail and Forums

13-Feb-05 5:22

ColdWaterBlue wrote:
Data Source=\\GUITARCHORD\LABTRACK

You don't need the two leading slashes in the server name.

Does this help?

Re: Connecting to SQL Server 2000 accross a Network

ColdWaterBlue13-Feb-05 5:26

ColdWaterBlue

13-Feb-05 5:26

I actually just figured it out myself. The two front slashes are not needed, but you need to add a user to the SQL Server (in my case, add the 'Guest' user) and give it administrative rights over the database. The User ID and Password are no longer needed, since the Integrated Security uses a trusted connection. Thanks anyway.

------------------------
ColdWaterBlue - Rock On

Re: Connecting to SQL Server 2000 accross a Network

Colin Angus Mackay13-Feb-05 5:27