Hi all
This code runs on IIS.7 in windows server 2008 R2 and MSSQL Server Express Edittion 2008 R2
this is a simple function which selects from the database based on 3 parameters and resturn object containing the selected row.

This code runs normally in most time, but in some cases it through exception called "serial_num ber" which is a column name in the database table.
Although i logged the 3 parameters...