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query issue

giuseppe D'Amico

Joined: Oct 04, 2011
Posts: 5
HI, I have a servlet that performs two differents query to a mysql db in function of the task,so only one at a time is used but one after the other in very fast sequence, each of them return a json, I have two identical methods parameters_list and potentials_list, but only parameters_list works properly the second one obtain from mysql an empty resultset, I can not figure why. Here it is the relevant code for the two methods:
Parameters_list is the working one

and the code for potentials_list that does not work

both methods
use a third one for json encoding

the two methods are the same apart the query and the key I use for the json to return, so do not understand whi potential_list obtain a void resultSet in queryDb4Potentials, I wish someone can help me,
thanks in advance
Jeanne Boyarsky
author & internet detective

Joined: May 26, 2003
Posts: 32811

What do you mean by "doesn't work." Does it throw an exception or just not return any data?

Also, there is a lot of code here. Could you try replying to this post by just showing what is different between the two examples?

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Abhinav Kansal

Joined: Jun 25, 2010
Posts: 5
Did you ran the query independently and saw the results? However the code looks alright.

I'm not sure why you have used two different methods for the same logic. I would suggest to modularize these methods and try running the core logic within a single method. To me, it just seems to be a problem with too much code duplication rather than some technical issue.
giuseppe D'Amico

Joined: Oct 04, 2011
Posts: 5
Thanks for your reply, I solved, just a stupid mistake.
I agree. Here's the link:
subject: query issue
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