Add null support for Decode function
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-4949-decode-null
Finally find a way to solve the null problem for Decode
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-4949-decode-null
Add a supposed failed tese case
Code review suggestions
Fix the type equal check bug for decode, Add second expression null case for decode
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-4949-decode-null
Finally fix to keep Hsql as what it is
Minor changes
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-4949-decode-null
Merge pull request #701 from VoltDB/ENG-4949-decode-null

Eng 4949 decode null