c# - Looking for a value in a column of many tables -

I have a way to return boolean to my repository, its job is to see the value that has been passed and See if that's the value in a table in their workers' column. For example:

  Public Bull ISPsernell KAP duplicate (string per_key) {var result = (From this point of view context.parson, where f.personnel_key == per_k select f). anyone (); Return result; }  

So in the same way I am looking at one of those tables. But to add to this method I have 20 more tables. What is a good way to do this? Do you suggest that I write a big "OR" of all these ". (") Statements "?

Thank you.

If LINQ is posted like a post like you, then you can use it: then Yes this is the way to go, but if you are very incompatible, then you will ask the database for N. If you can use the usual ADO and SQL commands, then you will only ask a question from the database and not the N times.