[DRILL-1838] MapVector should late bind/replace vector if current vector is null valued

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.7.0
• Assignee: Hanifi Gunes
• Reporter: Hanifi Gunes
• Created: 11/Dec/14 03:29
• Updated: 14/Dec/14 06:39
• Resolved: 14/Dec/14 06:39

Description

Assume we have two batches. The first one with all null values and the second one with a `concrete` value. Upon visiting the concrete value, we should replace the previous vector un-typed vector with the typed one to avoid a schema change exception.