tree 5caa40bd6e07158377f7ec9fc4f96a8c47ef40e7
parent 42006ad3324c778b3f3867079c9e75121c743c73
author chunhui-shi <cshi@maprtech.com> 1477816146 -0700
committer Aman Sinha <asinha@maprtech.com> 1480869305 -0800

DRILL-4982: Separate Hive reader classes for different data formats to improve performance.

1, Separating Hive reader classes allows optimization to apply on different classes in optimized ways. This  separation effectively avoid the performance degradation of scan.

2, Do not apply Skip footer/header mechanism on most Hive formats. This skip mechanism introduces extra checks on each incoming records.

close apache/drill#638