sandhyasun opened a new pull request #1780: [TRAFODION-3263]Changes to disable 
LOB locking and refactor IUD operations
URL: https://github.com/apache/trafodion/pull/1780
 
 
   The order of operations with this change is as follows :
   
   1.Call JNI hdfs Write API to write the lob data to hdfs. 
   2.Use return data offset from JNI hdfswrite API in 1. as the offset to store 
in the LOB descriptor tables. 
   3.If there are multiple chunks to write, do it in a loop and append to the 
first chunk. This way each chunk can be anywhere in hdfs and not necessarily 
continguous. But we are guaranteed that whatever we wrote will be stored in our 
internalLOB descriptor files.
   4. If any failure or TM erro occurs while writing to the LOB descriptor 
tables,  transaction gets rolled back and the chunk of hdfs data written 
becomes "dead data". It doesn't harm the next operation. 
   5. GC check is now done before an update or insert. Earlier it was done as 
part of the ::allocateDesc operation to get the EOD of the file. 

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