[DRILL-7796] Excel Reader Throws NPE with Blank Col in Middle

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.18.0
• Fix Version/s: 1.19.0
• Component/s: Storage - Text & CSV
• Assignee: Charles Givre
• Reporter: Charles Givre
• Created: 21/Oct/20 16:39
• Updated: 16/Dec/20 14:28
• Resolved: 16/Dec/20 14:28

Description

In working with some data, I discovered that if an Excel file contains a blank column in the middle of the dataset, the queries break. 

This fix corrects this issue.  Empty columns are treated as `FLOAT8`.