Correct this SQL Query: error "Microsoft Jet database engine cannot find the input table or query 'IF' "
i should say hi experts :D . Help me with this pretty code :)
The database:
"ID (Primary key)" | "Title"
0 | "title1" 1 | "title2" 2 | "title3" 3 | "title4"Sub AddRecord(ByVal Table As String, ByVal Columns As String, ByVal Record() As String)
Dim SubDir As String = ""
Dim Adapter As OleDbDataAdapter = New OleDbDataAdapter("SELECT * FROM " & Table, connectionString)
Dim command As OleDbCommand
Dim tbCorrectSyntax = ""
Using connection As New OleDbConnection(connectionString)
Try
connection.Open()
Dim Commandtxt As String = ""
For i = 0 To Record.GetUpperBound(0)
If Record(i).IndexOf(",") > 0 Then
Dim tmpRec() As String = Nothing
Dim cols() As String = Nothing
tmpRec = Record(i).Split(",")
cols = Columns.Split(",")
For j = 0 To tmpRec.GetUpperBound(0)
tbCorrectSyntax &= cols(j) & " = '" & tmpRec(j) & "' " & IIf(j = tmpRec.GetUpperBound(0), "", " , ")
Next
End If
Dim txtCorrect As String = IIf(tbCorrectSyntax = "", Columns & " = " & Record(i), tbCorrectSyntax)
Commandtxt = "IF OBJECT_ID ( 'InsertOrUpdateItem', 'P' ) IS NOT NULL " & _
"DROP PROCEDURE InsertOrUpdateItem " & _
"GO " & _
"CREATE PROCEDURE InsertOrUpdateItem " & _
"AS " & _
"IF (EXISTS (SELECT * FROM " & Table & _
" WHERE " & txtCorrect & "))" & _
" begin " & _
开发者_开发百科 "UPDATE (" & Table & ") " & _
txtCorrect & _
" WHERE " & txtCorrect & " " & _
" End " & _
" else " & _
" begin " & _
" INSERT INTO " & Table & " (" & Columns & ") " & _
" VALUES (" & Record(i) & ")" & _
" End " & _
"End "
'Commandtxt = "INSERT INTO " & Table & " (" & Columns & ") VALUES (" & Record(i) & ")"
command = New OleDbCommand(Commandtxt, connection)
command.CommandType = CommandType.StoredProcedure
command.ExecuteNonQuery()
Next
Catch ex As Exception
msgbox(ex.Message)
Finally
connection.Close()
End Try
End Using
End Sub
Function connectionString() As String
Return "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & DBdir & ";User Id=admin;Password=;"
End Function
The first procedure is a wrapper to add data to database fields (if the data doent exist) But update it the row with new data already exist.
Input:
Table = TableName Columns = name of colomns that will be updated separated by comma (Ex1: "ID" , Ex2: "ID,Title,...") Record() = string array that represent the new values( multiple values are separated with comma)OK, before adding values to database, we should check if a row exists with this values :)
TO do this, creating a Stored Procedure is a best way to deal with the database fastly.So... The problem now is, at the runtime, Miss OleDB throw this error:
Microsoft Jet database engine cannot find the input table or query 'IF' ....Thanks in advance :D
command.CommandType = CommandType.StoredProcedure
You are claiming you are running a stored proc (CommandText would be the name of an existing SProc). What you are actually giving it an SQL command to be executed directly. The CommandType should be Text;
I found a solution for my problem (with a little net research :) ) hahahaha i m happy
anyway, the initial question was: 'How to update a record in database if it exists'
So i tryed to create and store a Stored procedure in the database... but... :)
Then i found an interesting Method: the ExecuteScalar of OleDBcommand Class
It simply return a value according to Sql input : in the following example that i used, it return the index (primary key) if the recod exists. So lets begin:
Function GetRecordIndex(ByVal Table As String, ByVal Columns As String, ByVal Record As String) As String
Dim Commandtxt As String = ""
Dim Command As OleDbCommand
Dim tbCorrectSyntax As String = ""
Dim tbCorrectSyntaxAND As String = ""
Using connection As New OleDbConnection(connectionString)
Try
connection.Open()
If Record.IndexOf(",") > 0 Then
Dim tmpRec() As String = Nothing
Dim cols() As String = Nothing
tmpRec = Record.Split(",")
cols = Columns.Split(",")
For j = 0 To tmpRec.GetUpperBound(0)
tbCorrectSyntax &= cols(j) & "='" & tmpRec(j) & "' " & IIf(j = tmpRec.GetUpperBound(0), "", " , ")
tbCorrectSyntaxAND &= cols(j) & "='" & tmpRec(j) & "' " & IIf(j = tmpRec.GetUpperBound(0), "", " AND ")
Next
End If
Dim txtCorrect As String = IIf(tbCorrectSyntax = "", Columns & "=" & Record, tbCorrectSyntax)
Dim txtCorrectAND As String = IIf(tbCorrectSyntaxAND = "", Columns & "=" & Record, tbCorrectSyntaxAND)
Commandtxt = "SELECT * FROM " & Table & " WHERE " & txtCorrectAND
Command = New OleDbCommand(Commandtxt, connection)
Dim RecordIndex As String = Command.ExecuteScalar
Return RecordIndex
Catch ex As Exception
Return Nothing
Finally
connection.Close()
End Try
End Using
End Function
As before, Columns Parameter can be a single Database column, or multiple columns separated with comma . same thing with Record that represent the data inside each column
Thank for your help
Fadelovesky
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