Database

Re: Problem populating table

5-Jan-06 20:45

TheJudeDude wrote:
But isn't the connection open fron the form??

I don't know - Did you open it before calling this method? As a rule it is better not to keep a connection hanging around, it is better to create a new connection, open it, perform the data operations then close it again and let .NET's connection pooling handle how long the physical connection hangs around for. I recommend creating a method whose purpose is to create the connection, then call that method to get your connection.

In fact, and I know this is getting further from your original problem, I would recommend that you refactor all your data access in to its own class (at least) or assembly. This keeps all the data access code together and you can benefit from being able to easily reuse common methods (like opening a connection).

ColinMackay.net
"Man who stand on hill with mouth open will wait long time for roast duck to drop in." -- Confucius
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell

TheJudeDude7-Jan-06 3:30

TheJudeDude

7-Jan-06 3:30

Well, I got it done yesterday. I ended up making the connection programmaticly, and modifying the stored procedure and it worked. One little quirk is on the form. I have two blank labels and a progress bar. The progress bar works fine. I pass two variables to the labels inside a for loop and while loop. The problem is that the text is not showing in the labels....odd. Any insight?

Re: Problem populating table

Colin Angus Mackay7-Jan-06 3:42

7-Jan-06 3:42

TheJudeDude wrote:
I ended up making the connection programmaticly

How else would you make the connection?

TheJudeDude wrote:
The progress bar works fine. I pass two variables to the labels inside a for loop and while loop. The problem is that the text is not showing in the labels....odd. Any insight?

Probably because of its nature the progress bar updates the display immediately when its value is changed without waiting for paint event to fire, while the label control won't update the display until it gets a paint event, while a long task is in progress the message pump isn't firing events. You can force the label, or any control, to Refresh()[^] or you can call Application.DoEvents()[^] in order to process any other events (like button clicks, moving the scroll bar, etc.)

ColinMackay.net
"Man who stand on hill with mouth open will wait long time for roast duck to drop in." -- Confucius
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell

SQL query

Deian5-Jan-06 4:33

Deian

5-Jan-06 4:33

Hello,

I'm a newbie at SQL, I can't figure out how to make the following query:

I have table 1 (2 columns)

code|otherstuff

And table 2 (2 columns)

code|some other stuff.

I'm getting the DISTINCT code, and in the same query I want to get the count(*) of records in table1 for each code, and count(*) in table2 where the code equals the code in table1. Tried already all kinds of joins but to no avail.

Any suggestions? Confused | :confused:

Re: SQL query

Colin Angus Mackay5-Jan-06 6:39

5-Jan-06 6:39

Deian wrote:
I'm getting the DISTINCT code

This will be

SELECT DISTINCT code FROM Table1

Deian wrote:
and in the same query I want to get the count(*) of records in table1 for each code

We can drop the DISTINCT because we'll be adding a GROUP BY for the aggregation

SELECT code, COUNT(*) as count FROM Table1 GROUP BY code

Deian wrote:
count(*) in table2 where the code equals the code in table1

Now, create a similar query for Table2 and make both subqueries and join on the subqueries.

SELECT t1.code, count1, count2
FROM (SELECT code, COUNT(*) as count1                 -- This select is from the previous step
      FROM Table1
      GROUP BY code) AS t1
INNER JOIN (SELECT code, COUNT(*) as count2           -- Similar but for Table2
            FROM Table1
            GROUP BY code) AS t2 ON t1.code = t2.code -- Join the two subqueries together

Does this help?

ColinMackay.net
"Man who stand on hill with mouth open will wait long time for roast duck to drop in." -- Confucius
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell

Re: SQL query

Deian5-Jan-06 7:32

Deian

5-Jan-06 7:32

Thank YOU!

I guess you are my saviour Smile | :)

Re: SQL query

Deian6-Jan-06 5:22

Deian

6-Jan-06 5:22

Hello again!

The query works perfect in newer servers which support subqueries, but it don't work in my case (MySQL 3.23.58). Subqueries were introduced since MySQL 4.1.

How can I rewrite your query without using subqueries in order to get the count of records in both tables? Confused | :confused:

Thank you in advance!

-- modified at 11:22 Friday 6th January, 2006

Join On Null??

tadhg885-Jan-06 3:05

tadhg88

5-Jan-06 3:05

Hi i am havin a bit of trouble with the joins in this query as some of the values stored in the main table may be entered into the table as nulls so
when i try to join the another table using these values it will not work an i dont get back any rows does anyone have any ideas how to solve this problem

Thanks in advance Tim

select IsNull(p.firstName+ ' ','') + IsNull(p.MiddleName+ ' ','') + IsNull(p.LastName,'') as Name, i.Diagnosis as Injury,
SUBSTRING(CAST(i.Date as nvarchar), 0 ,12) as Date, im2.Name as Prognosis, imgoi.Name as GradOfInjury, impob.Name as PartOfBody,
imtt.Name as TissueType, imact.Name as Activity, imsur.Name as Surface, imsurcon.Name as SurfaceCondidtions, imfw.Name as Footwear,
'Recovered' = CASE WHEN i.Date IS NOT NULL and (i.DateRecovered IS NULL)
THEN 'No' ELSE 'Yes' END from injury i

join Person p on p.Id = i.PersonID
join InjuryMapping im2 on im2.ID = i.Prognosis
join InjuryMapping imgoi on imgoi.ID = i.GradeOfInjury
join InjuryMapping impob on impob.ID = i.PartOfBody
join InjuryMapping imtt on imtt.ID = i.TissueType
join InjuryMapping imact on imact.ID = i.Activity
join InjuryMapping imsur on imsur.ID = i.Surface
join InjuryMapping imsurcon on imsurcon.ID = i.SurfaceConditions
join InjuryMapping imfw on imfw.ID = i.Footwear

where (p.ID = 3 and i.ID = 87) or (p.ID = 7 and i.ID = 82)
order by p.Lastname

Re: Join On Null??

Colin Angus Mackay5-Jan-06 3:28

MSDE 2000 upgrade to SQL Server 2005 Developer

5-Jan-06 3:28

Use an OUTER JOIN, a LEFT OUTER JOIN or a RIGHT OUTER JOIN - Also, it is often better to write INNER JOIN rather than just JOIN as it makes the intent clearer.

ColinMackay.net
"Man who stand on hill with mouth open will wait long time for roast duck to drop in." -- Confucius
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell

Re: Join On Null??

tadhg885-Jan-06 4:42

tadhg88

5-Jan-06 4:42

nice one thanks alot

Kevin McFarlane5-Jan-06 2:34

Kevin McFarlane

5-Jan-06 2:34

I have MSDE 2000 on my system. I have a boxed version of VS 2005 Pro, which comes with SQL server 2005 Developer.

I installed VS Pro but chose to exclude SQL Server 2005 Express.

Then I tried installing SQL Developer. It complains that SQL Database Services (which I assume is the basic SQL Server Engine) cannot be installed, as there's no upgrade from MSDE 2000 to SQL Developer.

What's the recommended way of doing this? Get SQL Express to upgrade the MSDE and then install SQL Developer? Or just uninstall MSDE 2000 first? I'd prefer the former if possible.

Reason I opted not to install Express is because various people have reported issues with subsequently going to one of the the full SQL Servers.

On my laptop I did go for the default VS install, followed by SQL Server Developer. This went fine, but there was no previous MSDE database on my laptop. It did, however, miss out Management Studio initially, so I had to run the install again.

Kevin

Problem with connection pooling

nguyenvhn4-Jan-06 15:51

nguyenvhn

4-Jan-06 15:51

Dear all,

I have a problem with connection pooling. I programmed in VB.NET with ADO.NET and SQL Server. Here is my code in one form:

Dim conn as new SqlConnection(strConnectionString)
conn.Open
....
conn.Close

There are 3 SqlConnection instance in my code.

But If I run the form several times (about 25 times), it occurred an error: Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached

I am sure that I have closed conn as soon as posible, so I do not know why that error happend.

Any comment are welcome.

Thanks for reading.

Re: Problem with connection pooling

S. Akif Kamal4-Jan-06 18:21

S. Akif Kamal

4-Jan-06 18:21

It will only be caused if you have some connection left open

Akif

Re: Problem with connection pooling

nguyenvhn5-Jan-06 16:09

nguyenvhn

5-Jan-06 16:09

Thanks for answering. At last, I found the source of problem, beacause I turn on SQL Debuging mode in Visual Studio IDE. If I turn off that mode, the problem did not apprear again.

Thanks

kindly help me vb codes..

Estong Odpaga4-Jan-06 13:11

Estong Odpaga

4-Jan-06 13:11

how to import a data (.xls) in sqlserver using vb codes. tnx in advance.

september

-- modified at 19:35 Wednesday 4th January, 2006

Re: kindly help me vb codes..

ramani.r5-Jan-06 1:31

ramani.r

5-Jan-06 1:31

Hi u try this

Private Sub Command1_Click()
Dim con As New ADODB.Connection
Dim sqlcon As New ADODB.Connection
Dim rs As New ADODB.Recordset
' Excel sheet
Path = "C:\ramani\book1.xls"
ssql = "Provider=Microsoft.jet.oledb.4.0;Data Source=" & Path & ";Extended Properties=Excel 8.0"
If con.State = 1 Then con.Close
con.Open ssql

ssql = "select * from [sheet1$]"
If rs.State = 1 Then rs.Close
rs.Open ssql, con

'Sql server
ssql = "Provider=sqloledb;Data Source=IBMX225;Initial Catalog=Master;User Id=sa;Password=;"
If sqlcon.State = 1 Then sqlcon.Close
sqlcon.Open ssql
While Not rs.EOF
sstr = "insert into excel values(" & rs(0) & ",'" & rs(1) & "')"
sqlcon.Execute sstr
rs.MoveNext
Wend
End sub

-ramani

Connect to a CSV file

gharry4-Jan-06 10:58

4-Jan-06 10:58

I use this code to setup a connection to a CSV file:

ConnectionString = "Provider=Microsoft.Jet.OleDb.4.0;Data Source=" & Server.MapPath("Sql\C_Registered_horses.csv") & ";Extended Prperties=""text;HDR=Yes;FMT=Delimited"""
Dim QuerySQL As String
QuerySQL = "SELECT * FROM C_Registered_horses.csv"
Dim objConn As New OleDbConnection(ConnectionString)
Dim objCmd As OleDbCommand

objCmd = New OleDbCommand
objCmd.CommandText = QuerySQL
objCmd.Connection = objConn

But when i execute the objConn.Open() i get the error:

System.Data.OleDb.OleDbException: Could not find installable ISAM

Any idea's

S Douglas4-Jan-06 19:32

4-Jan-06 19:32

Im guessing the problem is with the connection string.

snipt from ADO Connection Strings[^]
strConnection = _T("Driver={Microsoft Text Driver (*.txt; *.csv)};"
"Dbq=C:\\DatabasePath\\;Extensions=asc,csv,tab,txt;");
If you are using tab delimited files, you must create the schema.ini file, and you must inform the Format=TabDelimited option in your connection string.

for more help with connection strings see ConnectionStrings.com/[^]

ZeePain! wrote:
This seems like one of those programs that started small, grew incrementally, building internal pressure, and finally barfed all over its source code sneakers. Or something.

thedailywtf.com[^]

-- modified at 1:34 Thursday 5th January, 2006

gharry4-Jan-06 23:01

4-Jan-06 23:01

I am sorry to say but using:
ConnectionString = "Driver={Microsoft Text Driver (*.txt; *.csv)};Dbq=" & Server.MapPath("Sql\") & ";Extensions=asc,csv,tab,txt;"

gives a error:
An OLE DB Provider was not specified in the ConnectionString. An example would be, 'Provider=SQLOLEDB;'.

What does the _T mean on the start of the sequence

S Douglas4-Jan-06 23:49

4-Jan-06 23:49

taken from connectionstrings.com

"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\txtFilesFolder\;Extended Properties=""text;HDR=Yes;FMT=Delimited"""

"HDR=Yes;" indicates that the first row contains columnnames, not data

Hmm, I see this is VB.NET, right? First example wont work. Hows this work?

Connection="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & Server.MapPath("/Sql\") & ";Extended Properties=""text;HDR=Yes;FMT=Delimited"""

ZeePain! wrote:
This seems like one of those programs that started small, grew incrementally, building internal pressure, and finally barfed all over its source code sneakers. Or something.

thedailywtf.com[^]

gharry4-Jan-06 23:59

4-Jan-06 23:59

Seems i forgot somehow the extra "". Would think that these extra's might not work in a string. It now works thanks

S Douglas5-Jan-06 0:02

5-Jan-06 0:02

Your welcome.

The extra "" are escape quotes so it includes one of the quotes as part of the string. Without those it doesnt get a fully qualified string (for the oledb connection)

I always love helping people with languages I haven't seen. Smile | :)

ZeePain! wrote:
This seems like one of those programs that started small, grew incrementally, building internal pressure, and finally barfed all over its source code sneakers. Or something.

thedailywtf.com[^]

gharry5-Jan-06 0:09

5-Jan-06 0:09

Now i would like to display all the data in a Datagrid using:
Try
objConn.Open()

dg1.DataSource = objCmd.ExecuteReader()
dg1.DataBind()
objConn.Close()

Catch Err As Exception
ltlError.Text = Err.ToString()

Finally
objConn.Close()

End Try
but i only get the first column and not the 4 other. How come.

S Douglas5-Jan-06 0:26