Databases!!!

Databases!!!

• Brick IM Robot

  well actually, my problem is that I need to check for strings in a database and then select a ramdom response from another database, thas is my specific problem, but in order to do that, I need to know how to wok with databases without using the controls right . just pure code!! if you can help me that would be awesome!
  

• John D Wilson

  //I have to go one by one comparing the strings

  No, that would be the slow way to do it.

  Dim QueryString As String = "SELECT Orders FROM Table1 where Orders LIKE '%fish%'"

  would return any order that contained the word 'fish'. LIKE uses % as a wildcard. You can also use =, as in

  Select * from Table1 where OrderID = 12 AND Order = 'Fish and chips'

  So, with a where clause, you use single quotes for strings, and no quotes for numbers.

  
  
  

• SathyaKV

  Hello Again!

  I have a problem trying to enum the records, I'm using this cod

  Public Function GetRowValue(ByVal QueryCount As String) As Integer

  Dim NumValue As Integer

  Using Conn As New OleDbConnection(ConnectionString)

  Dim command As New OleDbCommand(QueryCount, Conn)

  command.Connection.Open()

  NumValue = command.ExecuteScalar()

  End Using

  Return NumValue

  End Function

  The the Example Table is:

  ID Work

  1 Painter

  2 Farmer

  3 Doctor

  4 Teacher

  ...

  ...

  1000 Student

  Im usin this Command

  "SELECT COUNT(Wprk) FROM Jobs"

  whit smaller tables this code works but with this table doesn't, is there any other way

  
  

• MarkAtherton

  Thanks for tip, I'm going to use this code you gave me!!. it's very helpfull.

  I can use the READ statement as a True indicator right like

  If Reader.Read Then

  'Here goes the procedure!

  End If

  
  

• Jeek

  one more thing you use reader to put text in your textbox, i don't think this is a good idea

  for example if your reader have 10 records to read , your textbox will just show up the last one and you lose the rest, try to use other control that can contain a collection

  hope this helps

  
  
  

• Stormsys

  I believe so, yes.

  
  
  

• Toby Sharp

  I imagine the code in this article will cover what you want to know, there's lots of similar articles on that site as well:

  http://www.codeproject.com/vb/net/atcl.asp

  
  
  

• MatrixObjects

  hi,

  i think you are right, but the point is what you want to do will need lots of explanation , so i guess its better to review this page first and if anything stopped you we are here to help

  http://msdn2.microsoft.com/en-us/library/ms171918(VS.80).aspx

  to be able to deal with Access Database use OleDb not SQLClient http://msdn2.microsoft.com/en-us/library/system.data.oledb.aspx

  Connecting and Retrieving Data in ADO.NET >>> http://msdn2.microsoft.com/en-us/library/ms254937.aspx

  hope this helps

  
  
  

• SteveNash72

  I hear you.

  I work with Access Databases in VB 2005. What specific questions do you have

  
  
  

• justncase80

  Hey there, the information you game me is very good, I'm working right now in the database, but I have only one more Question..

  Is there any way that I can sear into a databes for a string cause I'm using the next code:

  Dim ConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Sample.mdb"

  Dim QueryString As String = "SELECT Orders FROM Table1"

  Using Connection As New OleDbConnection(ConnectionString)

  Dim Command As New OleDbCommand(QueryString, Connection)

  Connection.Open()

  Dim Reader As OleDbDataReader = Command.ExecuteReader

  While Reader.Read

  '****************************

  ' Then I use here the compare method that is not typed yet

  TextBox.Text = (Reader.GetString(1))

  '*********************************

  End While

  Reader.Close()

  End Using

  So my question is that if I can use other method than the READ one to make this happend or I have to go one by one comparing the strings

  Thanks for all your help!!.

  
  

• Steve at Clemson

  Now, Renee, you knew you couldn't go and say something like that and not have me completely disagree with you

  Not using SQL to access data would be the same as buying a car and pushing it to work. Absolutely do NOT do this unless you have religious reasons for not using SQL. SQL is how databases work. No matter how small your task, it is always going to be slower to do it by iterating through tables in code, even if you don't notice. You'd do better to do the job using the best tools, and not establishing any bad habits.

  Plus, a line of SQL is easier to write than a page of code.

  
  
  

• Prashant Utekar

  That SQL looks fine, have you tried COUNT(*) Also, what do you mean by it doesn't work, what happens

  If no record is ever deleted, you can

  select MAX(ID) from Jobs

  
  
  

• swivel

  Hey thaks for the reply

  the message error is this:

  "Error de sintaxis en la clausula FROM"

  Bbut I cant use, Count(*) because I have more that one column in the table, and I only need the row count for that colum, something like the next table

  ID Work Study

  1 painter yes

  2 farmer no

  3 doctor "this field and the next ones to 1000 are empty"

  ...

  1000 teacher

  
  

• Pingel

  Yes, I would agree with you and I'd recommend not bothering with SQL to do this.

  Take it in steps.

  Open the Database(s) with ADO.NET.

  Get the tables

  Itterate through them in that order.

  It's very simple.

  
  
  
• Databases!!!