Обсуждение: How to html-decode a html-encoded field

I have a table with a varchar field, such a field is HTML ENCODED. So, for example, the string "PLAIN WHITE T'S" is saved as "PLAIN WHITE T''S" (double quotes are not part of the string, I use them for clarity only). I need to perform a SELECT statement on this table and get the values HTML DECODED and I wonder if there is a function that I can include in such a statement for this purpose, for example "SELECT htmldecode(fld1) FROM table1". I will appreciate anu comments about my issue.

Hello

see http://postgres.cz/wiki/PostgreSQL_SQL_Tricks#Function_for_decoding_of_url_code

Regards

Pavel Stehule

2012/4/10 JORGE MALDONADO <jorgemal1960@gmail.com>:
> I have a table with a varchar field, such a field is HTML ENCODED. So, for
> example, the string "PLAIN WHITE T'S" is saved as "PLAIN WHITE T''S"
> (double quotes are not part of the string, I use them for clarity only). I
> need to perform a SELECT statement on this table and get the values HTML
> DECODED and I wonder if there is a function that I can include in such a
> statement for this purpose, for example "SELECT htmldecode(fld1) FROM
> table1". I will appreciate anu comments about my issue.
>
> Respectfully,
> Jorge Maldonado

On 2012-04-10, JORGE MALDONADO <jorgemal1960@gmail.com> wrote:
> --000e0ce0d2ee43edb104bd553408
> Content-Type: text/plain; charset=ISO-8859-1
>
> I have a table with a varchar field, such a field is HTML ENCODED. So, for
> example, the string "PLAIN WHITE T'S" is saved as "PLAIN WHITE
> T''S" (double quotes are not part of the string, I use them for
> clarity only). I need to perform a SELECT statement on this table and get
> the values HTML DECODED and I wonder if there is a function that I can
> include in such a statement for this purpose, for example "SELECT
> htmldecode(fld1) FROM table1". I will appreciate anu comments about my
> issue.

if you don't mind gettin an exception or the wrong answer on invalid 
input you can abuse xpath thusly:

with sample as ( values ('magic'),('s&witch'),('toaster')) 
select  column1 as input , (xpath('/z/text()', ('<z>'|| column1 ||'</z>')::xml))[1] as output 
from sample     
-- 
⚂⚃ 100% natural