Bug #93370 MySqlParameterCollection.Add precondition check isn't consistent

• Submitted: 27 Nov 2018 17:20
• Modified: 25 Oct 2022 17:09
• Reporter: Bradley Grainger (OCA)
• Status: Closed
• Category: Connector / NET
• Severity: S3 (Non-critical)
• Version: 8.0.13
• OS: Windows (10)
• CPU Architecture: Other (x64)

[27 Nov 2018 17:20] Bradley Grainger

Description:
MySqlParameterCollection.Add checks if a named parameter has already been added, but it throws inconsistently based on the order in which parameters are added. For example, assume that `cmd` is a MySqlCommand object.

cmd.Parameters.AddWithValue("foo", 1);
cmd.Parameters.AddWithValue("foo", 2);
^ throws MySqlException: Parameter 'foo' has already been defined.

cmd.Parameters.AddWithValue("foo", 1);
cmd.Parameters.AddWithValue("@foo", 2);
^ throws MySqlException: Parameter '@foo' has already been defined.

cmd.Parameters.AddWithValue("@foo", 1);
cmd.Parameters.AddWithValue("@foo", 2);
^ throws MySqlException: Parameter '@foo' has already been defined.

cmd.Parameters.AddWithValue("@foo", 1);
cmd.Parameters.AddWithValue("foo", 2);
^ doesn't throw

The last example should be consistent with the first three and throw a MySqlException that "Parameter 'foo' has already been defined."

How to repeat:
Run the following C# code:

using (var connection = new MySqlConnection("..."))
{
	connection.Open();
	using (var cmd = connection.CreateCommand())
	{
		cmd.Parameters.AddWithValue("@foo", 1);
		cmd.Parameters.AddWithValue("foo", 2);
		// expect exception to be thrown but it isn't
	}
}

[28 Nov 2018 6:12] MySQL Verification Team

Hello Bradley,

Thank you for the report and test case.
Observed with VS 2017 (C#.Net) and Connector/NET 8.0.13 version.

regards,
Umesh

[23 Sep 2022 18:10] Omar Chavez

Posted by developer:
 
Verified using Connector/Net version 8.0.30

[21 Oct 2022 18:12] Omar Chavez

Posted by developer:
 
This patch changes how the verification of an existing parameter is made in the MySqlParameterCollection.Add method

[25 Oct 2022 17:09] Christine Cole

Posted by developer:
 
Fixed as of the upcoming MySQL Connector/NET 8.0.32 release, and here's the proposed changelog entry from the documentation team:

Improved validation now ensures that the MySqlParameterCollection.Add()
method behaves consistently when it checks whether a named parameter has
been added already.

Thank you for the bug report.