Regular Expressions 101

Pro

Group 1(\s\\n)

\sany whitespace character

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

nthe literal n (110₁₀ / 156₈ / 6E₁₆) (case sensitive)

.*any character (except for line terminators), repeated any number of times

Group 2(PostgreSQL version 10)

PostgreSQL version 10the literal text PostgreSQL version 10 (case sensitive)

Group 3(.*?(\\n\s)){2}

{2}repeats the group contents below exactly 2 times:

.*?any character (except for line terminators), repeated any number of times

Group 4(\\n\s)

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

nthe literal n (110₁₀ / 156₈ / 6E₁₆) (case sensitive)

\sany whitespace character

Global pattern flags

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

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

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

(\s\\n).*(PostgreSQL version 10)(.*?(\\n\s)){2}

New

In most cases regexp_matches() should be used with the g flag, since if you only want\n the first match, it''s easier and more efficient to use regexp_match(). \nHowever, regexp_match() only exists in PostgreSQL version 10 and up. When working in older\n versions, a common trick is to place a regexp_matches() call in a sub-select, for\n example:\n