1. #494 #478 fix the bug that the setLocale function return wrong value to cause both the TDengine and Shell fail to launch 2. #642 add druid pool support 3. #643 when aggregating by days, the calculation doesn't start from 00:00:000 in this day 4. #645 multi-db switch may cause the table created in a wrong database 5. #657 RPC module frees the msg body while other threads still access that struct to cause the SIGSEGV error. 6. #659 importing history data which spans multiple files may cause head file corrupte 7. #660 non-atomic allocating cache block and inserting data into cache block cause the check data in cache failure 8. #677 no client can connect to server since no free sessions available