Does Parameter Order Matter in OleDbCommand Queries Using Question Mark Placeholders?

OleDbCommand Parameter Order and Priorities

In an attempt to debug a query for 40 minutes, it was discovered that the order of parameters plays a crucial role. The query in question is as follows:

SELECT * FROM tblSomething WHERE id = @id AND debut = @dtDebut AND fin = @dtFin

However, when the parameters were added in the following order:

cmd.Parameters.Add("@id", OleDbType.Integer).Value = idSociete;
cmd.Parameters.Add("@dtFin", OleDbType.Date).Value = dateTraitementFin;
cmd.Parameters.Add("@dtDebut", OleDbType.Date).Value = dateTraitementDebut;

no results were returned. Reversing the order of @dtDebut and @dtFin resolved the issue.

It was initially assumed that named parameters were introduced to avoid such ordering dependencies. However, according to MSDN:

The OLE DB .NET Provider does not support named parameters for passing parameters to an SQL statement or a stored procedure called by an OleDbCommand when CommandType is set to Text. In this case, the question mark (?) placeholder must be used.

Therefore, it is essential to maintain the correct order of parameters when using the OleDbCommand with parameters specified using the question mark placeholder.

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