[SPARK-4856] [SQL] NullType instead of StringType when sampling against empty string or nul...#3708

Closed

chenghao-intel wants to merge 2 commits intoapache:masterfrom chenghao-intel:json

+29-1

Commits on Dec 16, 2014

NullType instead of StringType when sampling against empty string or null value
chenghao-intel
committed

Commits on Dec 17, 2014

add more concise unit test
chenghao-intel
committed