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System.Data.OleDb.OleDbException: 'Syntax error (missing operator) in query expression '=1-'.'/
I got an error message in the code below:
VB.NET
Imports System.Data.OleDb
Public Class Form2
    Private Sub Bts_Click(sender As Object, e As EventArgs) Handles Bts.Click
        Dim conn As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\monja\Documents\Database7.accdb")
        conn.Open()

        Dim cmd As New OleDbCommand(" select RoomName, Location, Information from table1 where=" + TBs.Text + "", conn)
        Dim myreader As OleDbDataReader = cmd.ExecuteReader

        myreader.Read()

        TBr1.Text = myreader("Location")
        TBr2.Text = myreader("Information")
    End Sub
End Class


What I have tried:

I checked the MS access database. And I googled.
Posted
Updated 3-Nov-22 3:04am
v2

Try a query like this:
SELECT RoomName, Location, Information from table1 where Location=1

and use parameterized queries, otherwise your code will be vulnerable to SQL injection attacks.
See: Using Parameterized Queries and Reports in VB.NET Database Applications | CodeGuru[^]
 
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v2
This is a bigger problem than you thought ...

Never concatenate strings to build a SQL command. It leaves you wide open to accidental or deliberate SQL Injection attack which can destroy your entire database. Always use Parameterized queries instead.

When you concatenate strings, you cause problems because SQL receives commands like:
SQL
SELECT * FROM MyTable WHERE StreetAddress = 'Baker's Wood'
The quote the user added terminates the string as far as SQL is concerned and you get problems. But it could be worse. If I come along and type this instead: "x';DROP TABLE MyTable;--" Then SQL receives a very different command:
SQL
SELECT * FROM MyTable WHERE StreetAddress = 'x';DROP TABLE MyTable;--'
Which SQL sees as three separate commands:
SQL
SELECT * FROM MyTable WHERE StreetAddress = 'x';
A perfectly valid SELECT
SQL
DROP TABLE MyTable;
A perfectly valid "delete the table" command
SQL
--'
And everything else is a comment.
So it does: selects any matching rows, deletes the table from the DB, and ignores anything else.

So ALWAYS use parameterized queries! Or be prepared to restore your DB from backup frequently. You do take backups regularly, don't you?
 
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