[SPARK-28451] substr returns different values

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 3.0.0
• Component/s: Tests
• Assignee: Unassigned
• Reporter: Yuming Wang
• Created: 19/Jul/19 13:02
• Updated: 12/Dec/22 18:11
• Resolved: 29/Dec/19 11:56

Description

PostgreSQL:

postgres=# select substr('1234567890', -1, 5);
 substr
--------
 123
(1 row)

postgres=# select substr('1234567890', 1, -1);
ERROR:  negative substring length not allowed

Spark SQL:

spark-sql> select substr('1234567890', -1, 5);
0
spark-sql> select substr('1234567890', 1, -1);

spark-sql>