[DRILL-3509] Empty JSON files trigger exception when used in a union

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Cannot Reproduce
• Affects Version/s: 1.1.0
• Fix Version/s: 1.2.0
• Component/s: Query Planning & Optimization
• Assignee: Sean Hsuan-Yi Chu
• Reporter: Stefán Baxter
• Created: 17/Jul/15 09:51
• Updated: 04/Nov/15 23:48
• Resolved: 24/Jul/15 00:26

Description

When the right hand side of a union is a directory search that involving an empty json file (or a empty log file waiting for first log lines) causes this exception:
{
"errorMessage" : "PARSE ERROR: From line 1, column 564 to line 1, column 574: Column 'occurred_at' not found in any table\n\n\n[Error Id: bef7370a-3c4e-4c35-8126-33c391ecb8ce on localhost:31010]"
}

where 'occurred_at' is the first column used/requested.

This works fine if no union is involved but it happens regardless of the left/right position of the directory search if union is being called.