How to fix parameterized query error

The error message indicates that the command being executed expects a parameter named @l_code, but that parameter is not actually being supplied to the database engine at execution time.

In ADO/ADO.NET, this usually happens when:

1. The parameter name in the SQL text does not exactly match the parameter name in the Parameters collection (including spelling and any leading @).
2. The command object already has a parameter collection defined (for example, from a previous prepared/parameterized command), and the current CommandText does not match that parameter definition.

To fix the issue, ensure that:

1. The parameter name is consistent everywhere:

      Command1.CommandText = "INSERT INTO execsum (execsum_id, user_name, l_code) " &
                             "VALUES (@execsum_id, @user_name, @l_code)"
      
      Command1.Parameters.Clear() ' important if Command1 is reused
      Command1.Parameters.AddWithValue("@execsum_id", ExecSum_Id)
      Command1.Parameters.AddWithValue("@user_name", strUser_Name)
      Command1.Parameters.AddWithValue("@l_code", Location)
   

2. Location has a valid value (not missing or uninitialized) before executing the command.

If the same Command1 object is reused for multiple different SQL statements, always call Command1.Parameters.Clear() before adding parameters for the new statement so that the parameter list matches the current CommandText.

References:

• Command object parameters
• ActiveCommand property example (VB)
• Using Parameterized Queries with the SqlDataSource (VB)
• Issuing a Parameterized Query