get_regex¶
Description¶
Returns a string that matches the given regular expression (which may be null if nothing matches.) There are two optional parameters: a capture group parameter to specify which group to capture and a string parameter to specify flags:
c - Enables case-sensitive matching (default.)
i - Enables case-insensitive matching.
m - Enables multi-line mode (i.e. meta-characters ^ and $ match the beginning and end of any line of the input string.) By default, multi-line mode is disabled (i.e. ^ and $ match the beginning and end of the entire input string.)
s - Enables the POSIX wildcard character
.
to match\n
(newline.) By default,.
does not match\n
.
For more about regular expression syntax, see POSIX extended regular expressions.
Return type¶
string
Domain¶
This is a scalar function (calculates a single output value for a single input row.)
Categories¶
Usage¶
get_regex( input_string, pattern [ , occurrence ] [ , flags ] )
Argument |
Type |
Required |
Multiple |
---|---|---|---|
input_string |
string |
Required |
Only one |
pattern |
regex |
Required |
Only one |
occurrence |
int64 |
Optional |
Only one |
flags |
string |
Optional |
Only one |
Examples¶
filter get_regex(log, /er*or/) = 'error'
Filter rows from the input column log
where the regex capture matches ‘error’.