[HIVE-24565] Implement standard trim function

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Component/s: Parser, UDF
• Labels: pull-request-available
• Target Version/s: 4.0.0
• Assignee: Krisztian Kasa
• Reporter: Krisztian Kasa
• Created: 23/Dec/20 16:30
• Updated: 10/Jan/21 04:00
• Resolved: 08/Jan/21 13:38

Description

<trim function> ::=
TRIM <left paren> <trim operands> <right paren>

<trim operands> ::=
[ [ <trim specification> ] [ <trim character> ] FROM ] <trim source>

<trim source> ::=
<character value expression>

<trim specification> ::=
LEADING
| TRAILING
| BOTH

<trim character> ::=
<character value expression>

Example

SELECT TRIM(LEADING '0' FROM '000123');
123

Issue Links

• relates to: HIVE-24599 Add support vectorized two parameter trim functions
• relates to: HIVE-24598 Trim function should return null if any of its parameter is null
• links to: GitHub Pull Request #1810