Search Postgresql Archives

Re: Empty arrays vs. NULLs, 9.1 & 8.3

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 06/14/2012 03:54 PM, Ken Tanzer wrote:
Thanks Steve. FWIW I looked at the 9.0 and 9.1 release notes, and didn't find much on arrays in them.
The notes are terse (a 1-2 line comment encapsulates the results of hundreds of messages covering a couple year) but there are many references to updates in how arrays are handled.

I do have one follow-up curiosity question, though. Why does array_dims(array[]::varchar[]) return NULL instead of 0? I would expect NULL for a NULL array, but not an empty one. (And the same for array_[upper,lower,length] functions as well.
I can't answer, specifically. But it makes a certain amount of sense. An empty array has no elements so where does it "begin" or "end" - especially since PostgreSQL array indexes don't need to start at 1 and the array could be multi-dimensional. Unknown, aka null, seems the best response.

Cheers,
Steve


--
Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Postgresql Jobs]     [Postgresql Admin]     [Postgresql Performance]     [Linux Clusters]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Postgresql & PHP]     [Yosemite]
  Powered by Linux