Unused sql options is any harm?

Question

Consider the following code:

Dim sql = "SELECT * FROM MyTable WHERE value1 = @Param1"

If someCondition Then
   sql = sql + " AND value2 = @Param2"
End If

Dim cmd As New SqlCommand(sql, conn)
cmd.Parameters.AddWithValue("@Param1", param1Value)
cmd.Parameters.AddWithValue("@Param2", param2Value)

Assuming I built a complex sql statement dynamically that may or may not include a parameter @Param2- is there any harm in adding it to the command as a parameter?

My real use case is obviously much more complicated than that, but overall this is a pattern that I should avoid; and if so, why?

Answer 1

The only thing I would like to note is the fact that if you call .AddWithValue, you leave it to SQL Server to figure out what the data type of the parameter will be.

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:

SqlParameter aParam = new SqlParameter("@Param1", SqlDbType.VarChar, 50);
aParam.Value = param1Value;

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Answer 2

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