Re: array_length(anyarray)

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От
Marko Tiikkaja
Тема
Re: array_length(anyarray)
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52CED78B.3050703@joh.to
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array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) David Fetter <david@fetter.org>
Re: array_length(anyarray) Pavel Stehule <pavel.stehule@gmail.com>
Re: array_length(anyarray) Dean Rasheed <dean.a.rasheed@gmail.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Dean Rasheed <dean.a.rasheed@gmail.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Dean Rasheed <dean.a.rasheed@gmail.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Dean Rasheed <dean.a.rasheed@gmail.com>
Re: array_length(anyarray) Dean Rasheed <dean.a.rasheed@gmail.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Pavel Stehule <pavel.stehule@gmail.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Pavel Stehule <pavel.stehule@gmail.com>
Re: array_length(anyarray) Robert Haas <robertmhaas@gmail.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Pavel Stehule <pavel.stehule@gmail.com>
Re: array_length(anyarray) Florian Pflug <fgp@phlo.org>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Jim Nasby <jim@nasby.net>
Re: array_length(anyarray) Florian Pflug <fgp@phlo.org>
Re: array_length(anyarray) Merlin Moncure <mmoncure@gmail.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Dean Rasheed <dean.a.rasheed@gmail.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Merlin Moncure <mmoncure@gmail.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Merlin Moncure <mmoncure@gmail.com>
Re: array_length(anyarray) Florian Pflug <fgp@phlo.org>
Re: array_length(anyarray) Merlin Moncure <mmoncure@gmail.com>
Re: array_length(anyarray) Florian Pflug <fgp@phlo.org>
Re: array_length(anyarray) Andrew Dunstan <andrew@dunslane.net>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) Andrew Dunstan <andrew@dunslane.net>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
Re: array_length(anyarray) David Johnston <polobo@yahoo.com>
Re: array_length(anyarray) Marko Tiikkaja <marko@joh.to>
On 1/9/14 5:44 PM, Florian Pflug wrote:
> On Jan9, 2014, at 14:57 , Dean Rasheed  wrote:
>> On 19 December 2013 08:05, Pavel Stehule  wrote:
>>> length should be irrelevant to fact so array starts from 1, 0 or anything
>>> else
>>
>> Yes, this should just return the number of elements, and 0 for an empty array.
>
> +1. Anything that complains about arrays whose lower bound isn't 1 really
> needs a *way* less generic name than array_length().

Problem is, if you're operating on an array which could have a lower 
bound that isn't 1, why would you look at the length in the first place?  You can't access any elements by index, you'd need to look at 
array_lower().  You can't iterate over the array by index, you'd need to 
do  array_lower() .. array_lower() + array_length(), which doesn't make 
sense.  And then there's the myriad of stuff you can do with unnest() 
without actually having to look at the length.  Same goes for 
multi-dimensional arrays: you have even less things you can do there 
with only a length.

So if we give up these constraints, we also make this function 
completely useless.


Regards,
Marko Tiikkaja


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