FENNEL:  fix savepoint bug with empty DML
FENNEL:  fix savepoint bug with empty DML

[git-p4: depot-paths = "//open/dt/dev/": change = 3197]

LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb