[ARROW-16035] [Java] Arrow to JDBC ArrowVectorIterator with does not terminate with empty result set

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 7.0.0
• Fix Version/s: 9.0.0
• Component/s: Java
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/31454
• Assignee: Todd Farmer
• Reporter: Jonathan Swenson
• Created: 26/Mar/22 00:55
• Updated: 11/Jan/23 11:41
• Resolved: 03/May/22 12:06

Description

Using an ArrowVectorIterator built from a JDBC Result Set that is empty causes the iterator to never terminate. 

ArrowVectorIterator iterator =
    JdbcToArrow.sqlToArrowVectorIterator(conn.createStatement()
        .executeQuery("select 1 from table1 where false"), config); 

 

It appears as though this is due to the implementation of the hasNext() method.

The expectation is that the `isAfterLast()` method on a JDBC result set return true when the result set is empty. However, according to the JDBC documentation it will always return false when the result set is empty. 

Returns:true if the cursor is after the last row; false if the cursor is at any other position or the result set contains no rows

 

Issue Links

• is related to: ARROW-16529 [Java] Remove dependency on optional JDBC ResultSet method
• links to: GitHub Pull Request #13049
• links to: GitHub Pull Request #13107