Re: Array behavior oddities

"Bruce Momjian" <bruce(at)momjian(dot)us> writes:

> Tom Lane wrote:
>> Why do you find that surprising? It's either a slice or it isn't,
>> there's no halfway point. Are you proposing to throw an error if only
>> some of the subscripts have colons? What would be the point?
>
> What is confusing is if I see [1:3][2], I assume that is [1:3][2:2], not
> [1:3][1:2]. By what logic does [2] mean from 1 to 2?

Here's something else which confused me just now. Why does the second query
return NULL instead of an array slice?

postgres=# select (array['{foo}'::text[],'{bar}'])[1][1];
array
-------
foo
(1 row)

postgres=# select (array['{foo}'::text[],'{bar}'])[1];
array
-------

(1 row)

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Gregory Stark
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