Обсуждение: How to find the position of a characted in a string

2008/12/8 ss_postgres <ss.postgres@gmail.com>:
> Hi,
>
> I am trying to find the position of a character in a string which appears
> multiple times.
>
> The POSITION function returns the position of the character when it first
> occurs.
>
> For eg:
>
> select position ( ' ' in 'Hi How are you');
>
> This returns the result as "3".
>
>
> But i need to result to be
> 3
> 7
> 11
>
>
> Can anyone please let me know what would be the best way to do this.
>
> Thanks
>

My first things:

merlin=> select distinct(x.case) from (select (case when substring('Hi
How are you' from r for 1) = ' ' then r else null  end)  from
generate_series(0, length('Hi How are you')) as r) as x;
 case
------
    3
    7
   11


--
Pawel Socha

2008/12/8 ss_postgres <ss.postgres@gmail.com>:
>
>
> On Mon, Dec 8, 2008 at 5:44 PM, Pawel Socha <pawel.socha@gmail.com> wrote:
>>
>> 2008/12/8 ss_postgres <ss.postgres@gmail.com>:
>> > Hi,
>> >
>> > I am trying to find the position of a character in a string which
>> > appears
>> > multiple times.
>> >
>> > The POSITION function returns the position of the character when it
>> > first
>> > occurs.
>> >
>> > For eg:
>> >
>> > select position ( ' ' in 'Hi How are you');
>> >
>> > This returns the result as "3".
>> >
>> >
>> > But i need to result to be
>> > 3
>> > 7
>> > 11
>> >
>> >
>> > Can anyone please let me know what would be the best way to do this.
>> >
>> > Thanks
>> >
>>
>> My first things:
>>
>> merlin=> select distinct(x.case) from (select (case when substring('Hi
>> How are you' from r for 1) = ' ' then r else null  end)  from
>> generate_series(0, length('Hi How are you')) as r) as x;
>>  case
>> ------
>>    3
>>    7
>>   11
>>
>>
>> --
>> Pawel Socha
>
>
> Hi Pawal,
>
> Thanks a lot.
>
> Suppose i need to do the same thing on a column in a table, can you please
> let me know how to write the query.
Just create function ;)
> Also how to eliminate the null result at the end?  For eg: Running the above
> query gives 4 rows, the last row with null value.
select distinct(x.case) from (select (case when substring('Hi How are
you' from r for 1) = ' ' then r else null end) from generate_series(0,
length('Hi How are you')) as r) as x where x.case is not null;
> Thanks for your help.
>
>



--
Serdecznie pozdrawiam

Pawel Socha
pawel.socha@gmail.com

programista/administrator

perl -le 's**02).4^&-%2,).^9%4^!./4(%2^3,!#+7!2%^53%2&**y%& -;^[%"`-{
a%%s%%$_%ee'