PERFORMANCE: optimize common case in matches (PORegex)
------------------------------------------------------
Key: PIG-965
URL: https://issues.apache.org/jira/browse/PIG-965
Project: Pig
Issue Type: Improvement
Components: impl
Reporter: Thejas M Nair
Some frequently seen use cases of 'matches' comparison operator have follow
properties -
1. The rhs is a constant string . eg "c1 matches 'abc%' "
2. Regexes such that look for matching prefix , suffix etc are very common. eg
- "abc%', "%abc", '%abc%'
To optimize for these common cases , PORegex.java can be changed to -
1. Compile the pattern (rhs of matches) re-use it if the pattern string has not
changed.
2. Use string comparisons for simple common regexes (in 2 above).
The implementation of Hive like clause uses similar optimizations.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
