[DRILL-7116] Adapt statistics to use Drill Metastore API

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.16.0
• Fix Version/s: 1.16.0
• Assignee: Vova Vysotskyi
• Reporter: Vova Vysotskyi
• Created: 19/Mar/19 15:43
• Updated: 10/Apr/19 08:41
• Resolved: 10/Apr/19 08:41

Description

The current implementation of statistics supposes the usage of files for storing and reading statistics.
The aim of this Jira is to adapt statistics to use Drill Metastore API so in future it may be stored in other metastore implementations.

Implementation details:

• Move statistics info into TableMetadata
• Provide a way for obtaining TableMetadata in the places where statistics may be used (partially implemented in the scope of DRILL-7089)
• Investigate and implement (if possible) lazy materialization of DrillStatsTable.