NETCOOL regular expression library

If your system supports single-byte character languages, you can use the NETCOOL regular expression library to run search queries on your data. The NETCOOL library provides better system performance than the TRE regular expression library.

Note: When a regular expression is written in SQL, the SQL parser first processes string literals before passing them to the regular expression library. The SQL parser processes backslash sequences, so single backslashes will not subsequently be seen by the regular expression library. Therefore, when you write a regular expression in SQL, use double backslashes to escape reserved characters.

For example, to escape the parentheses in the string '1_(22)', use this expression: '1_\$22\$'.

The NETCOOL regular expression library supports the use of normal characters and metacharacters. The following table describes the set of metacharacters supported by the NETCOOL regular expression library.

Table 1. Metacharacters
Metacharacter	Description	Examples
`*`	Matches zero or more instances of the preceding atom. Matches as many instances as possible.	`goo*` matches `my godness`, `my goodness`, and `my gooodness`, but not `my gdness`.
`+`	Matches one or more instances of the preceding atom. Matches as many instances as possible.	`goo+` matches `my goodness` and `my gooodness`, but not `my godness`.
`?`	Matches 1 or zero instances of the preceding atom.	`colou?r` matches `color` and `colour`. `end-?user` matches `enduser` and `end-user`.
`$`	Matches the end of the string.	`end$` matches `the end`, but not `the ending`.
`^`	Matches the beginning of the string.	`^severity` matches `severity level 5`, but not `The severity is 5`.
`.`	Matches any single character.	`b.at` matches `baat`, `bBat`, and `b4at`, but not `bat` or `bB4at`.
`[abcd]`	Matches any character in the square brackets.	`[nN][oO]` matches `no`, `nO`, `No`, and `NO`. `gr[ae]y` matches both spellings of the word ’grey’; that is, `gray` and `grey`.
`[a-d]`	Matches any character in the range of characters separated by a hyphen (`-`).	`[0-9]` matches any decimal digit. `[ab3-5]` matches `a`, `b`, `3`, `4`, and `5`. `^[A-Za-z]+$` matches any string that contains only upper or lowercase characters.
`[^abcd]` `[^a-d]`	Matches any character except those in the square brackets or in the range of characters separated by a hyphen (`-`).	`[^0-9]` matches any string that does not contain any numeric characters.
`()`	Indicates that the characters within the parentheses should be treated as a character pattern.	`A(boo)+Z` matches `AbooZ`, `AboobooZ`, and `AbooboobooZ`, but not `AboZ` or `AboooZ`. `Jan(uary)?` matches `Jan` and `January`.
`\|`	Matches one of the atoms on either side of the pipe character.	`A(B\|C)D` matches `ABD` and `ACD`, but not `AD`, `ABCD`, `ABBD`, or `ACCD`. `(AB \| CD)` matches `AB` and `CD`, but not `ABD` and `ACD`.
`\`	Indicates that the metacharacter following should be treated as a regular character. The metacharacters listed in this table require a backslash escape character as a prefix to switch off their special meaning.	`\` matches the `` character. `\\` matches the `\` character. `\.` matches the `.` character. `\[[0-9 ]*\]` matches an opening square bracket, followed by any digits or spaces, followed by a closed bracket.