From: Reggie Burnett
Date: September 26 2004 7:08am
Subject: RE: Return parameter from query.
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Out, intout, and return parameters are only supported when dealing with
stored procedures in 5.0 and later.  For what you are doing, you should
not use a parameter.  See this code.

MySqlCommmand cmd =3D new MySqlCommand("SELECT MAX(ID) FROM myTable",
conn);
Object max =3D cmd.ExecuteScalar();

HTH,
Reggie

-----Original Message-----
From: Asbj=F8rn Konstad [mailto:asbjorn@stripped]=20
Sent: Friday, September 24, 2004 3:06 AM
To: dotnet@stripped
Subject: Return parameter from query.

Hi.

=20

Anyone as frustrated as me???

=20

Problem:

I have a created a command to return maximum id from myTable.., like
this:

=20

//----------------------------------------------------------------------
----
------------------------------------------------------------------------
----
-----

=20

MySqlCommand cmd =3D new MySqlCommand(=93SELECT @PAR :=3D MAX(ID) FROM
myTable=94,
myConnection);

MySqlParameter param =3D new MySqlParameter();

param =3D cmd.Parameters.Add(=93@PAR=94, MySqlDbType.Int32, 4);

param.Direction =3D ParameterDirection.Output;

=20

myConnection.Open();

  cmd.ExecuteNonQuery();

  int max_id =3D (int)cmd.Parameters[=93@PAR=94].Value;

myConnection.Close();

=20

//----------------------------------------------------------------------
----
------------------------------------------------------------------------
----
----

=20

This gives me an error -> =93error in SQL-Syntax=94.

I read the issue with use of =93?=94 instead of =93@=94, and I=92ve =
tried it
all=85=85!,
it keeps throwing exeptions like =93null values=94=20

=93Object reference not set to an instance of an object=94=85 and so on.

=20

Anyone have a fail-proof method of creating a command with
return-parameters??

=20

Thanks.

=20

Reg.

=20

Asbj=F8rn Konstad


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