[HIVE-24598] Trim function should return null if any of its parameter is null

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Labels: newbie pull-request-available
• Target Version/s: 4.0.0
• Assignee: Soubhik Chakraborty Assign to me
• Reporter: Krisztian Kasa
• Created: 07/Jan/21 09:32
• Updated: 05/Sep/22 12:00
• Resolved: 05/Sep/22 12:00

Description

Hive throws exception when null is passed as a parameter of trim/rtrim/ltrim

select trim(null);

org.apache.hadoop.hive.ql.parse.SemanticException: Line 1:7 Wrong arguments 'TOK_NULL': trim takes only STRING/CHAR/VARCHAR types. Found VOID

 

However null should be returned. From SQL11 standard:
a) Let S be the value of the <trim source>.
b) If <trim character> is specified, then let SC be the value of <trim character>; otherwise, let SC be

<space>.

c) If at least one of S and SC is the null value, then the result of the <trim function> is the null value.

Issue Links

• is related to: HIVE-24565 Implement standard trim function
• links to: GitHub Pull Request #3322