How to retrieve a random record of DPL EntityStore of a unit test?

Hello
I want to write my code integration and unit tests. I want to get something random an EntityStore? How would you do that?

If there is no direct way to get a random entry, is there a way to get an object by its position? In this way, I could determine the number and get a random input.

I write a lot of code tests of the DAO layer where I need an entry that will satisfy my foreign key relationships.

Thanks in advance,
Steven

Hi Steven,

The LPD only supports Btree (ordered key) databases. So the only access is key lookup (exact or approximate) and scanner sequentially (forward or backward).

You have probably thought about this, but one thing you can do is to get the keys of the first and the last and generates a random value between the two. Once you have generated a random key in the right range, you can approximate search of key using one of the methods entities() PrimaryIndex or SecondaryIndex.

Entities() methods have signatures that allow to specify a beginKey. If you specify the beginKey, and null for the endKey, then the first returned entity will be greater than or equal to the beginKey. This is how a rough key search is made.

-mark

Tags: Database

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