[SPARK-28076] String Functions: SUBSTRING support regular expression

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 3.0.0
• Component/s: SQL
• Assignee: Unassigned
• Reporter: Yuming Wang
• Created: 17/Jun/19 08:45
• Updated: 09/Jan/20 02:53
• Resolved: 09/Jan/20 02:53

Description

Function	Return Type	Description	Example	Result
substring(string from pattern)	text	Extract substring matching POSIX regular expression. See Section 9.7 for more information on pattern matching.	substring('Thomas' from '...$')	mas
substring(string from pattern for escape)	text	Extract substring matching SQL regular expression. See Section 9.7 for more information on pattern matching.	substring('Thomas' from '%#"o_a#"_' for '#')	oma

For example:

-- T581 regular expression substring (with SQL's bizarre regexp syntax)
SELECT SUBSTRING('abcdefg' FROM 'a#"(b_d)#"%' FOR '#') AS "bcd";

https://www.postgresql.org/docs/11/functions-string.html