UBB.Developers Forums Community Development Programming MySQL and Server Configuration Error in "Error Log"

I have a question about an error I have been getting in the "Error Log".

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Unable to do_query: SELECT B_Main,B_Board FROM w3t_Posts WHERE B_Number = - You have an error in your SQL syntax. Check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 3 [/]

What is wrong? Everything seems to be running smoothly, but this error is showing up on a daily basis in the error log.

Thanks,