Clone
Paul Rogers <par0328@yahoo.com>
committed
on 07 Oct
DRILL-7377: Nested schemas for dynamic EVF columns
The Result Set Loader (part of EVF) allows adding columns up-front
before reading rows (s… Show more
DRILL-7377: Nested schemas for dynamic EVF columns

The Result Set Loader (part of EVF) allows adding columns up-front

before reading rows (so-called "early schema.") Such schemas allow

nested columns (maps with members, repeated lists with a type, etc.)

The Result Set Loader also allows adding columns dynamically

while loading data (so-called "late schema".) Previously, the code

assumed that columns would be added top-down: first the map, then

the map's contents, etc.

Charles found a need to allow adding a nested column (a repeated

list with a declared list type.)

This patch revises the code to use the same mechanism in both the

early- and late-schema cases, allowing adding nested columns at

any time.

Testing: Added a new unit test case for the repeated list late

schema with content case.

Show less