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Posted to commits@cassandra.apache.org by sl...@apache.org on 2016/06/27 18:34:07 UTC
[12/34] cassandra git commit: Fix CQL doc (incomplete)
http://git-wip-us.apache.org/repos/asf/cassandra/blob/5d65542b/doc/source/operations.rst
----------------------------------------------------------------------
diff --git a/doc/source/operations.rst b/doc/source/operations.rst
index 31ecc35..cf8812f 100644
--- a/doc/source/operations.rst
+++ b/doc/source/operations.rst
@@ -19,11 +19,6 @@
Operating Cassandra
===================
-Replication Strategies
-----------------------
-
-.. todo:: todo
-
Snitch
------
@@ -264,12 +259,12 @@ tombstone that has not been propagated to all replicas and that could cause dele
To be able to drop an actual tombstone the following needs to be true;
-- The tombstone must be older than ``gc_grace_seconds``
-- If partition X contains the tombstone, the sstable containing the partition plus all sstables containing data older
+- The tombstone must be older than ``gc_grace_seconds``
+- If partition X contains the tombstone, the sstable containing the partition plus all sstables containing data older
than the tombstone containing X must be included in the same compaction. We don't need to care if the partition is in
an sstable if we can guarantee that all data in that sstable is newer than the tombstone. If the tombstone is older
than the data it cannot shadow that data.
-- If the option ``only_purge_repaired_tombstones`` is enabled, tombstones are only removed if the data has also been
+- If the option ``only_purge_repaired_tombstones`` is enabled, tombstones are only removed if the data has also been
repaired.
TTL
@@ -538,9 +533,9 @@ The primary motivation for TWCS is to separate data on disk by timestamp and to
more efficiently. One potential way this optimal behavior can be subverted is if data is written to SSTables out of
order, with new data and old data in the same SSTable. Out of order data can appear in two ways:
-- If the user mixes old data and new data in the traditional write path, the data will be comingled in the memtables
+- If the user mixes old data and new data in the traditional write path, the data will be comingled in the memtables
and flushed into the same SSTable, where it will remain comingled.
-- If the user's read requests for old data cause read repairs that pull old data into the current memtable, that data
+- If the user's read requests for old data cause read repairs that pull old data into the current memtable, that data
will be comingled and flushed into the same SSTable.
While TWCS tries to minimize the impact of comingled data, users should attempt to avoid this behavior. Specifically,