Sends a request to /v1/releases/latest?flavor=$CITUS_EDITION once a day,
which returns a response similar to {"version": "7.1.0", "major": 7,
"minor": 1, "patch": 0}. Then compares it with current Citus version,
and if the latest release is newer, logs a LOG message.
This includes:
(1) Wrap everything inside a StartTransactionCommand()/CommitTransactionCommand().
This is so we can access the database. This also switches to a new memory context
and releases it, so we don't have to do our own memory management.
(2) LockCitusExtension() so the extension cannot be dropped or created concurrently.
(3) Check CitusHasBeenLoaded() && CheckCitusVersion() before doing any work.
(4) Do not PG_TRY() inside a loop.
This commit makes a change in relay_event_utility.c to check if the
Alter Table command adds a constraint using index. If this is the
case, it appends the shard id to the index name.
By this commit, citus minds the replica identity of the table when
we distribute the table. So the shards of the distributed table
have the same replica identity with the local table.
Expands count distinct coverage by allowing more cases. We used to support
count distinct only if we can push down distinct aggregate to worker query
i.e. the count distinct clause was on the partition column of the table,
or there was a grouping on the partition column.
Now we can support
- non-partition columns, with or without grouping on partition column
- partition, and non partition column in the same query
- having clause
- single table subqueries
- insert into select queries
- join queries where count distinct is on partition, or non-partition column
- filters on count distinct clauses (extends existing support)
We first try to push down aggregate to worker query (original case), if we
can't then we modify worker query to return distinct columns to coordinator
node. We do that by adding distinct column targets to group by clauses. Then
we perform count distinct operation on the coordinator node.
This work should reduce the cases where HLL is used as it can address anything
that HLL can. However, if we start having performance issues due to very large
number rows, then we can recommend hll use.
This change introduces the `pg_dist_node_metadata` which has a single jsonb value. When creating
the extension, a random server id is generated and stored in there. Everything in the metadata table
is added as a nested objected to the json payload that is sent to the reports server.
The following scenario can cause an Assert() crash if we don't do this:
- Install Citus v7.0-15
- Restart server & run a query to start maintenanced.
- Install Citus v7.1
- Restart server & run a query. This will tell user to upgrade.
- Type "UPDATE EXTENSION c" & press tab. maintenanced will start and crash
with Assert(CitusHasBeenLoaded() && CheckCitusVersion(WARNING));
This change checks Citus version before calling metadata functions so the
crash doesn't happen.
This will provide the full project name (i.e. Citus/Citus Enterprise),
and the host system, compiler, and architecture word size.
I wanted to limit the number of copied files in 'config', so I added
only config.guess and call it manually, rather than using the macro
AC_CANONICAL_HOST, which requires several other files.
Eclipse apparently doesn't scan build output looking for -D flags, so
having the value actually appear in a header is nicer for those of us
using IDEs.
Previously <curl/curl.h> was included even if compiled --without-libcurl.
This can fail when libcurl headers are not there. This commit guards this
include by checks for HAVE_LIBCURL.
Adds ```citus.enable_statistics_collection``` GUC variable, which ```true``` by default, unless built without libcurl. If statistics collection is enabled, sends basic usage data to Citus servers every 24 hours.
The data that is collected consists of:
- Citus version
- OS name & release
- Hardware Id
- Number of tables, rounded to next power of 2
- Size of data, rounded to next power of 2
- Number of workers
This commit provides the support for window functions in subquery and insert
into select queries. Note that our support for window functions is still limited
because it must have a partition by clause on the distribution key. This commit
makes changes in the files insert_select_planner and multi_logical_planner. The
required tests are also added with files multi_subquery_window_functions.out
and multi_insert_select_window.out.
We should skip if the process blocked on the relation
extension since those locks are hold for a short duration
while the relation is actually extended on the disk and
released as soon as the extension is done. Thus, recording
such waits on our lock graphs could yield detecting wrong
distributed deadlocks.
We sent multiple commands to worker when starting a transaction.
Previously we only checked the result of the first command that
is transaction 'BEGIN' which always succeeds. Any failure on
following commands were not checked.
With this commit, we make sure all command results are checked.
If there is any error we report the first error found.
When a table and it's shards are dropped, and afterwards the same
shard identifiers are reused, e.g. due to a DROP & CREATE EXTENSION,
the old entry in the shard cache and the required entry in the shard
cache might be for different tables.
Force invalidation for both old and new table to fix.
Citus can handle INSERT INTO ... SELECT queries if the query inserts
into local table by reading data from distributed table. The opposite
way is not correct. With this commit we warn the user if the latter
option is used.
When a NULL connection is provided to PQerrorMessage(), the
returned error message is a static text. Modifying that static
text, which doesn't necessarly be in a writeable memory, is
dangreous and might cause a segfault.
With this commit, we relax the restrictions put on the reference
tables with subquery pushdown.
We did three notable improvements:
1) Relax equi-join restrictions
Previously, we always expected that the non-reference tables are
equi joined with reference tables on the partition key of the
non-reference table.
With this commit, we allow any column of non-reference tables
joined using non-equi joins as well.
2) Relax OUTER JOIN restrictions
Previously Citus errored out if any reference table exists at
any point of the outer part of an outer join. For instance,
See the below sketch where (h) denotes a hash distributed relation,
(r) denotes a reference table, (L) denotes LEFT JOIN and
(I) denotes INNER JOIN.
(L)
/ \
(I) h
/ \
r h
Before this commit Citus would error out since a reference table
appears on the left most part of an left join. However, that was
too restrictive so that we only error out if the reference table
is directly below and in the outer part of an outer join.
3) Bug fixes
We've done some minor bugfixes in the existing implementation.
If after the distributed deadlock detection decides to cancel
a backend, the backend has been terminated/killed/cancelled
externally, we might be accessing to a NULL pointer. This commit
prevents that case by ignoring the current distributed deadlock.
This is necessary for multi-row INSERTs for the same reasons we use it
in e.g. UPSERTs: if the range table list has more than one entry, then
PostgreSQL's deparse logic requires that vars be prefixed by the name
of their corresponding range table entry. This of course doesn't affect
single-row INSERTs, but since multi-row INSERTs have a VALUE RTE, they
were affected.
The piece of ruleutils which builds range table names wasn't modified
to handle shard extension; instead UPSERT/INSERT INTO ... SELECT added
an alias to the RTE. When present, this alias is favored. Doing the
same in the multi-row INSERT case fixes RETURNING for such commands.
This change adds support for SAVEPOINT, ROLLBACK TO SAVEPOINT, and RELEASE SAVEPOINT.
When transaction connections are not established yet, savepoints are kept in a stack and sent to the worker when the connection is later established. After establishing connections, savepoint commands are sent as they arrive.
This change fixes#1493 .
We should prevent running the deadlock detection if
there is a major version change. Otherwise, the daemon
may access to obsolete metadata catalog tables.
This change fixes a use-after-free bug while renaming obsolete
`pg_worker_list.conf` file, which causes Citus to crash during upgrade
(or even extension creation) if `pg_worker_list.conf` exists.
We added a new field to the transaction id that is set to true only
for the transactions initialized on the coordinator. This is only
useful for MX in order to distinguish the transaction that started
the distributed transaction on the coordinator where we could
have the same transactions' worker queries on the same node.
We added a new GUC citus.log_distributed_deadlock_detection
which is off by default. When set to on, we log some debug messages
related to the distributed deadlock to the server logs.
With this commit, the maintenance deamon starts to check for
distributed deadlocks.
We also introduced a GUC variable (distributed_deadlock_detection_factor)
whose value is multiplied with Postgres' deadlock_timeout. Setting
it to -1 disables the distributed deadlock detection.
We send SIGINT to a backend that is cancelled due to a deadlock. That
approach ends up being a very confusing error message.
With this commit we intercept the error messages and show a more
meaningful error message to the user.
Now that we already have the necessary infrastructure for detecting
distributed deadlocks. Thus, we don't need enable_deadlock_prevention
which is purely intended for preventing some forms of distributed
deadlocks.