Обсуждение: Simple method to format a string?

Good morning,

Is there a simply method in psql to format a string?

For example, adding a space to every three consecutive letters:

abcdefgh -> *** *** ***

Thanks a lot!
Emi

On Jun 20, 2012, at 7:43 AM, Emi Lu wrote:

> Good morning,
>
> Is there a simply method in psql to format a string?
>
> For example, adding a space to every three consecutive letters:
>
> abcdefgh -> *** *** ***
>
> Thanks a lot!
> Emi

I'm unaware of such a function (it seems like a generic format() function's arguments would be so complex as to be
almostunusable) but you can make use of locales to do some formatting for you. See
http://www.postgresql.org/docs/9.1/static/locale.html.

This pretty much calls for a user defined function.  Plpgsql should
work, but if you're more comfy in perl or tcl there's pl/tcl and
pl/perl you can try as well.

On Wed, Jun 20, 2012 at 8:43 AM, Emi Lu <emilu@encs.concordia.ca> wrote:
> Good morning,
>
> Is there a simply method in psql to format a string?
>
> For example, adding a space to every three consecutive letters:
>
> abcdefgh -> *** *** ***
>
> Thanks a lot!
> Emi
>
> --
> Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-general



--
To understand recursion, one must first understand recursion.

On 6/20/2012 12:59 PM, Scott Marlowe wrote:
> This pretty much calls for a user defined function.  Plpgsql should
> work, but if you're more comfy in perl or tcl there's pl/tcl and
> pl/perl you can try as well.
>
> On Wed, Jun 20, 2012 at 8:43 AM, Emi Lu <emilu@encs.concordia.ca> wrote:
>> Good morning,
>>
>> Is there a simply method in psql to format a string?
>>
>> For example, adding a space to every three consecutive letters:
>>
>> abcdefgh -> *** *** ***
>>
>> Thanks a lot!
>> Emi
>>
>> --
>> Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
>> To make changes to your subscription:
>> http://www.postgresql.org/mailpref/pgsql-general
>
>
>
This is the perl func I use:  sorry about the formatting


-- mask char is 0 (zero).  anything else gets copied across
create or replace function applyMask(text, text) returns text as $$
         my($mask, $src) = @_;

         my $srcAt = 0;
         my $srcLen = length($src);
         my $result = '';

         for my $i (0..length($mask)-1)
         {
                 my $mchar = substr($mask, $i, 1);
                 if ($mchar eq '0')
                 {
                         if ($srcAt >= $srcLen)
                         {
                                 $result .= ' ';
                         } else {
                                 $result .= substr($src, $srcAt, 1);
                                 $srcAt++;
                         }
                 } else {
                         $result .= $mchar;
                 }
         }
         return $result;
$$ language plperl;



For example:

select applyMask('(000) 000-0000', '1235551313');

Emi Lu wrote:
> Good morning,
>
> Is there a simply method in psql to format a string?
>
> For example, adding a space to every three consecutive letters:
>
> abcdefgh -> *** *** ***

Depending on how you want 'extras' handled, you could work from
something like this:

   select trim(regexp_replace('123456', '...', '\& ', 'g'));

If you don't care about trailing space remove the 'trim()'.

The replacement string may need to be escaped differently depending
on your PG version and setting for standard_conforming_strings.  For
example:  E'\\& '

HTH

Bosco.

>     select trim(regexp_replace('123456', '...', '\& ', 'g'));
>
> If you don't care about trailing space remove the 'trim()'.
>
> The replacement string may need to be escaped differently depending
> on your PG version and setting for standard_conforming_strings.  For
> example:  E'\\& '

After combined with several more replace(s), regexp_replace will provide
me the expecting result.

Thanks!
Emi

--
select
regexp_replace(
    replace(
        replace(col-val, ' ', ''), '-', ''),
         .... replace...
     '(...)', E'\\1 ', 'g')
from tn;