How to implement dynamic queries for MNesia?

Posted by Kerem on Stack Overflow See other posts from Stack Overflow or by Kerem
Published on 2010-06-11T08:59:53Z Indexed on 2010/06/11 9:02 UTC
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I'm trying to implement a function that generates dynamic queries for MNesia.

For example, when function is called with these arguments;

dyn_query(list, person, [name, age], ["jack", 21])

I want to query MNesia to list items whose name is "jack" and age is 21 in person table.

I've tried to implement this by using qlc:q(ListComprehension) and qlc:string_to_handle("ListComprehension"). First failed because of compile errors, compiler didn't let me to use functions instead of ListComprehentions and variables instead of record names like "Item#Table.Member". Second failed, because erl_eval couldn't handle records and throwed exceptions like {undefined_record, person}.

Which method should I use? How could i solve these problems? Or should I use a different method?

Thanks.

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