In transformations that support use of regex patterns, you may need to specify capture groups. A capture group is a pattern that describes a set of one or more characters that constitute a match.
This section contains information on how special capture group references are managed.
The dollar sign ($) is used as a form of escape character in the with
parameter of the replace
transform. This pattern identifies the replacement string.
In the table below, you can review how these replacement patterns are supported across the running environments.
Pattern | Description | On Photon | On Hadoop |
---|---|---|---|
$$ | Inserts a $ in the replacement value. | Yes | Yes |
$n or$nn | For non-negative digits n , this pattern inserts the nth parameterized sub-match string, provided that the first argument was a regex object. | Yes | Yes |
In the following example, the MyColumn
column contains the value foobar
in all rows.
source value | replace transform | replacement | |
---|---|---|---|
foobar |
| $foobar | |
foobar |
Note that the |
o
|