On 2021-11-28 00:27:34 +0000, Shaozhong SHI wrote:
> this is supposed to find those to have 2 words and more.
>
> select name FROM a_table where "STREET_NAME" ~ '^[[:alpha:]+ ]+[:alpha:]+$';
I think you meant
select name FROM a_table where "STREET_NAME" ~ '^[[:alpha:]+ ]+[[:alpha:]]+$';
Note the extra two brackets.
The character classes (like [:alpha:] or [:digit:] can only be used
within bracket expressions. So you have to put brackets around the
second [[:alpha:], too (like you did for the first one).
But if you look more closely at the first one, you will notice that it
doesn't do what you want, either: It matches any non-empty sequence of
alpabetic characters, plus signs and spaces. But you almost certainly
don't want to match a plus sign, and you don't want space and alphabetic
characters to be interchangable. You want some alphabetic characters
followed by a space. So this becomes
select name FROM a_table where "STREET_NAME" ~ '^([[:alpha:]]+ )+[[:alpha:]]+$';
hp
--
_ | Peter J. Holzer | Story must make more sense than reality.
|_|_) | |
| | | hjp@hjp.at | -- Charles Stross, "Creative writing
__/ | http://www.hjp.at/ | challenge!"
