* Keep track of cached entries in case of interruption.
Previously we set DistTableCacheEntry->sortedShardIntervalArray
and DistTableCacheEntry->shardIntervalArrayLength after we entered
all related shard entries into DistShardCacheHash. The drawback was
that if populating DistShardCacheHash was interrupted,
ResetDistTableCacheEntry() didn't see the shard hash entries created,
so was unable to clean them up.
This patch fixes that by setting sortedShardIntervalArray earlier,
and incrementing shardIntervalArrayLength as we enter shards into
the cache.
Fairly straightforward; verified that modifications fail atomically if
a worker is down or fails mid-transaction (i.e. all workers need to ack
modifications to reference tables in order to persist changes).
Including several examples from #1926. I couldn't understand why the
recover_prepared_transactions "should be an error", and EXPLAIN has
changed since the original bug (so that it runs EXPLAINs in txns, I
think for EXPLAIN ANALYZE to not have side effects); other than that,
most of the reported bugs now error out rather than crash or return
an empty result set.
VACUUM runs outside of a transaction, so the failure modes for it are
somewhat straightforward, though ANALYZE runs in a 1pc transaction and
multi-table VACUUM can fail between statements (PG 11 and higher).
Tests various failure points during a multi-shard modification within
a transaction with multiple statements. Verifies three cases:
* Reference tables (single shard, many placements)
* Normal table with replication factor two
* Multi-shard table with no replication
In the replication-factor case, we expect shard health to be affected
in some transactions; most others fail the transaction entirely and
all we need verify is that no effects of the transaction are visible.
Had trouble testing the final PREPARE/COMMIT/ROLLBACK phase of the 2pc,
in particular because the error message produced includes the PID of
the backend, which is unpredictable.
Drop schema command fails in mx mode if there
is a partitioned table with active partitions.
This is due to fact that sql drop trigger receives
all the dropped objects including partitions. When
we call drop table on parent partition, it also drops
the partitions on the mx node. This causes the drop
table command on partitions to fail on mx node because
they are already dropped when the partition parent was
dropped.
With this work we did not require the table to exist on
worker_drop_distributed_table.
PG now allows foreign keys on partitioned tables.
Each foreign key constraint on partitioned table
is propagated down to partitions.
We used to create all constraints on shards when we are creating
a new shard, or when just simply moving a shard from one worker
to another. We also used the same logic when creating a copy of
coordinator table in mx node.
With this change we create the constraint on worker node only if
it is not an inherited constraint.
We used to set the execution mode in the truncate trigger. However,
when multiple tables are truncated with a single command, we could
set the execution mode very late. Instead, now set the execution mode
on the utility hook.
By setting the CPU tuple cost so high, we were triggering JIT. Instead,
we should use parallel_tuple_cost.
See: rhaas.blogspot.com/2018/06/using-forceparallelmode-correctly.html
This reverts commit a2fb5a84f1.
JIT wasn't actually interfering with the operation of Citus, a test was
just written in a way which caused JIT to run for a function on every
row in a 150k-row table.
With this commit, we all partitioned distributed tables with
replication factor > 1. However, we also have many restrictions.
In summary, we disallow all kinds of modifications (including DDLs)
on the partition tables. Instead, the user is allowed to run the
modifications over the parent table.
The necessity for such a restriction have two aspects:
- We need to acquire shard resource locks appropriately
- We need to handle marking partitions INVALID in case
of any failures. Note that, in theory, the parent table
should also become INVALID, which is too aggressive.
We acquire distributed lock on all mx nodes for truncated
tables before actually doing truncate operation.
This is needed for distributed serialization of the truncate
command without causing a deadlock.
Reason for the failure is that PG11 introduced a new relation kind
RELKIND_PARTITIONED_INDEX to be used for partitioned indices.
We expanded our check to cover that case.
Sumedh Pathak
Hadi Moshayedi
Marco Slot
Jason Petersen
Burak Velioglu
velioglu
Önder Kalacı
Murat Tuncer
Murat Tuncer
Hadi Moshayedi
Marco Slot
Jason Petersen
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