I am using a data adapter to pull data from an access database (see below code). When I run the SQL in the Access database I get the expected data. However when I step through the code the fill method produces only the table definition but no rows.
I have used this procedure ma开发者_开发问答ny times in the past and it still works for those calls.
Again the SQL in access returns the correct data and in C# I don't get ANY error message but I don't get the data either. Had anyone seen this before?
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public void GetQueries(ref DataTable tSQL, String tool, string Filter, OleDbConnection lConn) { OleDbDataAdapter dadapt = new OleDbDataAdapter(); //Data Adapter for Access String lSQL = ""; //assign the connection to the processing mdb
//lAccProcSQL.Connection = lConn;
//Pull the queries to be executed
lSQL = "SELECT * FROM tblSQL WHERE Active = TRUE AND ToolCode = '" +
tool + "' and type not in (" + Filter + ") ORDER BY QueryNum";
//Set the adapter to point to the tblSQL table
dadapt = new OleDbDataAdapter(lSQL, lConn);
//clear tables in case of rerun
tSQL.Clear();
//Fill working queries data table
dadapt.Fill(tSQL);
}`
Are you sure that the filter that you've defined in the WHERE clause will evaluate to true on certain rows ?
Why don't you use parameters instead of string concatenation ? Are you sure that Active = True
will evaluate to true ? As far as I know, True is represented by -1 in Access.
So, why don't you try it like this:
var command = new OleDbCommand();
command.Connection = lConn;
command.CommandText = "SELECT * FROM tblSql WHERE Active = -1 AND ToolCode = @p_toolCode AND type NOT IN (" + filter + ") ORDER BY querynum";
command.Parameters.Add ("@p_toolCode", OleDbType.String).Value = tool;
datapt = new OleDbDataAdapter();
datapt.SelectCommand = command;
dadapt.Fill (tSql);
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