Question

The query does not return value when I call it from ASP C# however when I connect the MySQL server and type the same query it returns right values. I couldn’t discover the problem.

Here is the code segment:

try
{
    personquery = "select b.* from booking b, makes m  "+
                  "where m.personid="+ 
                  DataDeneme1.login.personid.ToString() +
                  "and m.bookingno=b.bookingno";
    con = new MySqlConnection(System.Configuration.ConfigurationManager.AppSettings.Get("connectionString"));
    cmd.CommandText = personquery;
    con.Open();
    cmd.Connection = con;
    adap = new MySqlDataAdapter(personquery, con);
    adap.Fill(ds);
    // CheckBoxList1.DataSource = ds;
    // CheckBoxList1.DataBind();
    GridView1.DataSource = ds;
    GridView1.DataBind();
    con.Close();
}
catch (Exception ex)
{
    Response.Write(ex.Message);
    Response.Write(ex.StackTrace);
}

The input and the output from mysql server:

mysql> select b.* from booking b, makes m  where m.personid=1 and m.bookingno=b.bookingno;
+-----------+-----------------+--------------+-------------+------------+-------------+  
| bookingno | reservationdate | dropoffplace | pickupplace | pickupdate | dropoffdate |  
+-----------+-----------------+--------------+-------------+------------+-------------+  
|         8 | 2011-05-09      | Ankara       | Ankara      | 2011-05-10 | 2011-05-15  |   
|         9 | 2011-05-09      | Ankara       | Ankara      | 2011-05-20 | 2011-05-25  |   
+-----------+-----------------+--------------+-------------+------------+-------------+  
2 rows in set (0.00 sec)  

and Exception message….

You have an error in your SQL syntax;
check the manual that corresponds to
your MySQL server version for the
right syntax to use near
‘m.bookingno=b.bookingno’ at line 1 at
MySql.Data.MySqlClient.MySqlStream.ReadPacket()
at
MySql.Data.MySqlClient.NativeDriver.GetResult(Int32&
affectedRow, Int32& insertedId) at
MySql.Data.MySqlClient.Driver.GetResult(Int32
statementId, Int32& affectedRows,
Int32& insertedId) at
MySql.Data.MySqlClient.Driver.NextResult(Int32
statementId) at
MySql.Data.MySqlClient.MySqlDataReader.NextResult()
at
MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior
behavior) at
MySql.Data.MySqlClient.MySqlCommand.ExecuteDbDataReader(CommandBehavior
behavior) at
System.Data.Common.DbCommand.System.Data.IDbCommand.ExecuteReader(CommandBehavior
behavior) at
System.Data.Common.DbDataAdapter.FillInternal(DataSet
dataset, DataTable[] datatables, Int32
startRecord, Int32 maxRecords, String
srcTable, IDbCommand command,
CommandBehavior behavior) at
System.Data.Common.DbDataAdapter.Fill(DataSet
dataSet, Int32 startRecord, Int32
maxRecords, String srcTable,
IDbCommand command, CommandBehavior
behavior) at
System.Data.Common.DbDataAdapter.Fill(DataSet
dataSet) at
DataDeneme1.customerview.loadList() in
E:\VisualStudioProjects\DataDeneme1\DataDeneme1\customerview.aspx.cs:line
38

Answer 1

I would bet it has to do with the dynamic value DataDeneme1.login.personid.ToString(), since the exception states the next piece of text. Ensure your value is what you are expecting, a blank/whitespace value would cause this error.

UPDATE
Based on you comment I saw what I believe to be the issue. If the value is 1 then the result of this:

personquery = "select b.* from booking b, makes m  "+
              "where m.personid="+ 
              DataDeneme1.login.personid.ToString() +
              "and m.bookingno=b.bookingno";

Would be:

select b.* from booking b, makes m
where m.personid=1and m.bookingno=b.bookingno

No space, so add that to the initial query creation:

personquery = "select b.* from booking b, makes m  "+
              "where m.personid= "+ 
              DataDeneme1.login.personid.ToString() +
              " and m.bookingno=b.bookingno";

Which would result in:

select b.* from booking b, makes m
where m.personid= 1 and m.bookingno=b.bookingno