In HBase Scans (and by extension Gets) do not retrieve deleted cells or the tombstone markers that mark them as deleted. Sometimes is useful for trouble shooting (or backup - there will be a separate blog post about that soon) to see all c
In HBase Scans (and by extension Gets) do not retrieve deleted cells or the tombstone markers that mark them as deleted.Here's an example of what it would look like in the shell:
hbase(main):001:0> scan 'x2', {RAW=>true, VERSIONS=>10}ROW COLUMN+CELL r1 column=f:c, timestamp=1323323611106, value=v3 r1 column=f:c, timestamp=1323323609988, type=DeleteColumn r1 column=f:c, timestamp=1323323609988, value=v2 r1 column=f:c, timestamp=1323323608554, value=v1 r2 column=f:c, timestamp=1323323617759, value=v3 r2 column=f:c, timestamp=1323323616226, value=v2 r2 column=f:c, timestamp=1323323614496, value=v1 2 row(s) in 0.6380 seconds
In this the above example values 'v2' and 'v1' for row key 'r1' have been deleted with a column delete marker.
hbase(main):005:0> scan 'x1', {RAW=>true, VERSIONS=>10}ROW COLUMN+CELL r2 column=f:, timestamp=1323323616226, type=DeleteFamily r2 column=f:c, timestamp=1323323617759, value=v3 r2 column=f:c, timestamp=1323323616226, value=v2 r2 column=f:c, timestamp=1323323614496, value=v1 2 row(s) in 0.0500 seconds
The sort order was carefully designed to allow HBase to identify all cells affected by a delete marker in single forward scan through the store files(s).
原文地址:HBase "Raw" scans, 感謝原作者分享。
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