Regexp search and replace functions. Adapted from regexp.old by Henry Spencer.
Provides following functions:
Checks if source string matches pattern.
sqlite> select true where 'the year is 2021' regexp '[0-9]+';
1
Checks if source string matches pattern.
sqlite> select regexp_like('the year is 2021', '[0-9]+');
1
sqlite> select regexp_like('the year is 2021', '2k21');
0
Returns source substring matching pattern.
sqlite> select regexp_substr('the year is 2021', '[0-9]+');
2021
sqlite> select regexp_substr('the year is 2021', '2k21');
Replaces matching substring with replacement string.
sqlite> select regexp_replace('the year is 2021', '[0-9]+', '2050');
the year is 2050
sqlite> select regexp_replace('the year is 2021', '2k21', '2050');
the year is 2021
Supports backreferences to captured groups \1 trough \9 in replacement string:
sqlite> select regexp_replace('the year is 2021', '([0-9]+)', '\1 or 2050');
the year is 2021 or 2050
The following regular expression syntax is supported:
X* zero or more occurrences of X
X+ one or more occurrences of X
X? zero or one occurrences of X
(X) match X
X|Y X or Y
^X X occurring at the beginning of the string
X$ X occurring at the end of the string
. Match any single character
\c Character c where c is one of \{}()[]|*+?.
\c C-language escapes for c in afnrtv. ex: \t or \n
[abc] Any single character from the set abc
[^abc] Any single character not in the set abc
[a-z] Any single character in the range a-z
[^a-z] Any single character not in the range a-z
sqlite> .load ./re
sqlite> select regexp_like('abcdef', 'b.d');