Select random row

Support
#1

I want to select any single random
I think this loads all the list and returns the first one.
dataManager.load(Organizations.class).all().one();
I need it to be just be a random one.

Thank you for the help !!

#2

This loads the first one returned by the database (using SQL limit 1):

dataManager.load(Organizations.class).all().maxResults(1).one();

#3

Performance would be an issue but one way to do it would be to load everything into a List, get the size of the list, then generate a random number between 0 and size of list, and use that to pull that entry out by index.

#4

Thanks you both for your reply.

Can you guys give me your opinion on this approach?

public Organization getRandom() {
        Integer rowCount = dataManager
                .loadValue("select count(e.id) from app_Organization e", Integer.class).one();
        return dataManager.loadValue("select e from app_Organization e", Organization.class)
                .firstResult(new Random().nextInt(rowCount + 1)).maxResults(1).one();
    }
#5

Looks good to me :slight_smile:

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