Regular Expressions 101

Pro

(?m)applies the following effective flags to the remainder of the pattern: gm

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

^start of line

Non-Capturing Group(?:--|[[:space:]]+)

1st Alternative--

--the literal text --

2nd Alternative[[:space:]]+

Character Class[[:space:]]+

+matches at least one character from the set below:

[:space:]a whitespace character, including a line break [ \t\r\n\v\f]

.+any character (except for line terminators), repeated at least once

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

(?m)^(?:--|[[:space:]]+).+

New

-- Query taken from:
-- https://stackoverflow.com/a/12467388/1655567
SELECT country.name as country, country.headofstate
from country
    -- Worst place to add comment ever
  -- Here is even uglier
inner join city on city.id = country.capital
where city.population > 100000
-- this comment makes no sense here and would break sql parser buyt hey
and country.headofstate like 'A%'
-- WOW!