[HIVE-11406] Vectorization: StringExpr::compare() == 0 is bad for performance

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.3.0, 2.0.0
• Fix Version/s: 1.3.0, 2.0.0
• Component/s: Vectorization
• Assignee: Matt McCline
• Reporter: Gopal Vijayaraghavan
• Created: 29/Jul/15 23:39
• Updated: 16/Feb/16 23:53
• Resolved: 04/Aug/15 18:09

Description

StringExpr::compare() == 0 is forced to evaluate the whole memory comparison loop for differing lengths of strings, though there is no possibility they will ever be equal.

Add a StringExpr::equals which can be a smaller and tighter loop.