This function iterates over lbidList (populated by an earlier call to
DBRM::getUncommittedExtentLBIDs()) to find those LBIDs which belong to
the AUX column. It then finds the corresponding LBIDs for all other columns
which belong to the same table as the AUX LBID and appends them to lbidList.
The updated lbidList is used by invalidateUncommittedExtentLBIDs() to update
the casual partitioning information.
DBRM::addToLBIDList() only comes into play in case of a transaction ROLLBACK.
by default), which when enabled, indiscriminately invalidates all
column extents and performs the actual DELETE only on the AUX
column. The trade-off with this approach would now be that the
first SELECT for certain query patterns (those containing a WHERE
predicate) after the DELETE operation will slow down as the
invalidated column extent would need to be scanned again to set
the min/max values.
In the joblist code, in addition to sending the lbid of the SCAN
column, we also send the corresponding lbid of the AUX column to PrimProc.
In the primitives processor code in PrimProc, we load the AUX column
block (8192 rows since the AUX column is implemented as a 1-byte
UNSIGNED TINYINT) into memory and then pass it down to the low-level
scanning (vectorized scanning as applicable) routine to build a non-Empty
mask for the block being processed to filter out DELETED rows based on
comparison of the AUX block row to the empty magic value for the AUX column.
the DELETE operation. ColumnOp::readBlock() calls can cause writes
to database files when the active chunk list in ChunkManager is full.
Since non-AUX columns are read-only for the DELETE operation, we prevent
writes of compressed chunks and header for these columns by passing
an isReadOnly flag to CompFileData which indicates whether the column
is read-only or read-write.
JobList low-level code relateod to primitive jobs now uses shared pointers instead of ByteStream refs talking to DEC
b/c same-node EM-PP communication now goes over a queue in DEC instead of a network hop.
PP now has a separate thread that processes the primitive job messages from that DEC queue.
