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ways to store results from query?

 
Shailan Mm
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Hi

I was wondering what the common ways to store the results of a JDBC query were. I have recently migrated from Perl, and am used to storing the results in a hash. Is there a similar data structure that can easily handle the results of the query. I have tried HashMap, but cant figure out how to get a key to map to another HashMap internally without explicitly creating the internal HashMaps first.

E.g.
The query is something like this:
select animal, type, name from animals;

and the result set is:

Animal Type Name
dog husky Bella
dog poodle Alfie
cat manc Gus

I want the data structure to look like this:

dog => {husky => Bella, poodle => Alfie}
cat => {manc => Gus}

that is:
1) 2 top level keys - dog and cat
2) the 'dog' key pointing to another HashMap which itself has 2 keys - husky and poodle, with the value for husky being Bella and the value for poodle, Alfie
3) the 'cat' key pointing to another HashMap containing one key-value pair, manc => Gus


Alternatively, is there some better way to store the results rather than trying to duplicate Perl hashes?

Thank you
Shailan
 
Jeanne Boyarsky
author & internet detective
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Shailan,
You are correct that you have to create the internal HashMaps first. But if you write one or two utility methods, this shouldn't be a big deal.

I typically store my results in an ArrayList because my applications don't have any need for the multiple levels you are trying for.
 
Shailan Mm
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Posts: 8
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Thanks Jeanne, and sorry for the cross post in the beginners forum.
 
It is sorta covered in the JavaRanch Style Guide.
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