Revert "Support COALESCE function in Spark SQL and Hive QL"

This reverts commit bbdeebe645d0f045d51b7e9e9adc379fbd7cdc55.
Revert "Revert "Support COALESCE function in Spark SQL and Hive QL""

This reverts commit f2ea39b68cb3965be3eeeb9e74794778e5b884a9.
updated