Optimized query for filtering nodes with a given depth

[bhavinkamani]

What is the best way to get all the nodes with a given depth. Currently, I do Node.all.select {|n| n.depth == 3}. This generates one query for each iteration which isn't very optimized.

[mceachen]

You'd want a named scope so you can do it in one select. Do you think this
would be generally useful to add to the library?

Matthew

On Sep 3, 2012, at 3:30 AM, Bhavin notifications@github.com wrote:

What is the best way to get all the nodes with a given depth. Currently, I
do Node.all.select {|n| n.depth == 3}. This generates one query for each
iteration which isn't very optimized.

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Reply to this email directly or view it on
GitHubhttps://github.com//issues/17.

[bhavinkamani]

Scope will do however having generic method such Tag.nodes(depth) will be cool.

I really liked this gem. I was also evaluating ltree Postgres Extension. I picked Closure Tree because it gives a more robust and SQL compliant non-proprietary approach and has super api. I also liked the fact that unlike ltree it retains the data integrity through foreign key association.

However, I do miss the querying ability of ltree. Would it make sense to use some of the ltree magic for postgres db behind the scene!!!

[mceachen]

This feature was released in version 3.5.0 just now. Search for find_all_by_generation in the readme.

[bhavinkamani]

That was really fast and very helpful :-). Thanks a lot for this beautiful gem.