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https://issues.apache.org/jira/browse/PHOENIX-1516?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14242481#comment-14242481
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Gabriel Reid commented on PHOENIX-1516:
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+1 to the idea of adding this kind of function.
It seems ok to me that it isn't possible to set a random seed -- in my own use
cases, setting a random seed is typically only useful for making sure that
something is totally deterministic, but it seems like there are enough things
going on all over the place (in different JVMs, different threads, etc), that
it would be difficult to ensure that we have a fully deterministic random value
coming out for each row.
The fact that the same random will be generated for multiple columns in the
same row seems like a bit of a show-stopper to me. As a user, I would expect
that multiple calls to RANDOM() will give multiple (different) random values.
One point that also is probably worth looking into is the creation of a new
Random() in each call to evaluate(). The default constructor of Random() calls
some code that has class-level locks, so there could be some lock contention if
multiple threads in the same JVM are calling {{new Random()}} over and over.
> Add RANDOM built-in function
> ----------------------------
>
> Key: PHOENIX-1516
> URL: https://issues.apache.org/jira/browse/PHOENIX-1516
> Project: Phoenix
> Issue Type: Bug
> Reporter: Lars Hofhansl
> Assignee: Lars Hofhansl
> Attachments: 1516.txt
>
>
> I often find it useful to generate some rows with random data.
> Here's a simple RANDOM() function that we could use for that.
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