count_regex_matches(input: storable, pattern: const regex, [position: const int64]?, [flags: const string]?) -> int64

Returns the number of times the given regular expression pattern occurs in the argument string.

There are two optional parameters:

• a position parameter to specify the number of characters from the beginning of the string where the function starts searching for matches
• 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.

Domain

This is a scalar function (calculates a single output value for a single input row).

Categories

• Regex

Examples

make_col dotted_quads_count:count_regex_matches(log, /[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}/)

Count all occurrences of four numbers (length 1-3 digits) separated by periods, from the input column log, into an int64 column named dotted_quads_count. If no such quads exist in the input log, then it returns 0.