Re: Referencing parts captured by round brackets in a regex in 8.4.13

On 22 March 2013 16:08, Alexander Farber <alexander(dot)farber(at)gmail(dot)com> wrote:

> Thank you, this works better, but -

> the result is correctly "true" now,
> but the warning is still there, why?
>
> # select 'axxxxxyz' ~ '(.)\\1\\1';
> WARNING: nonstandard use of \\ in a string literal
> LINE 1: select 'axxxxxyz' ~ '(.)\\1\\1';
> ^
> HINT: Use the escape string syntax for backslashes, e.g., E'\\'.
> ?column?
> ----------
> t
> (1 row)

Because backslash is not normally a valid escape character in an SQL string
literal.

You can turn off the warning in your settings, or you can be explicit about
wanting a string literal that can include such escape characters by using
the E'<string>' notation.

I seem to recall that there's a string literal notation specific to regular
expressions as well (R'<regular expression>'?), but I may be mixing up
databases...

--
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Cut the trees and you'll see there is no forest.