badlydrawnbhoy <badlydrawnbhoy@gmail.com> wrote:
> I hope this is the right forum for this, but please correct me if
> somewhere else is more appropriate.
>
> I need to locate all the entries in a table that match , but only after
> a number of characters have been ignored. I have a table of email
> addresses, and someone else has erroneously entered some addresses
> prefixed with 'mailto:', which I'd like to ignore.
>
> An example would be: john.smith@smiths.com should match
> mailto:john.smith@smiths.com
>
> I've tried the following
>
> select address
> from people
> where address = (select replace(address, 'mailto:', '') from people);
>
> which gives me the error
>
> ERROR: more than one row returned by a subquery used as an expression
There's no need to use a sub-select for this, this should do the job:
SELECT REPLACE(address, 'mailto:', '') FROM people;
You also have some options for "fuzzy" matching in the WHERE clause, e.g.
SELECT address FROM people WHERE address LIKE '%doom@%'
Will find all email addresses like "doom@...", whether or not there's a
'mailto:' prefix. (% matches any character string).
This will find all the records with the erroneous "mailto:" prefix:
SELECT address FROM people WHERE address LIKE 'mailto:%'
