Commit Graph

3158 Commits (26178fb53895e0fcaef53f27351caa0024c44fd8)

Author SHA1 Message Date
Jelte Fennema-Nio 26178fb538 Add missing postgres.h includes
After sorting includes in the previous commit some files were now
invalid because they were not including postgres.h
2024-04-17 10:26:50 +02:00
Jelte Fennema-Nio 48c62095ff Actually sort includes after cherry-pick 2024-04-17 10:26:50 +02:00
Nils Dijk 75df19b616 move pg_version_constants.h to toplevel include (#7335)
In preparation of sorting and grouping all includes we wanted to move
this file to the toplevel includes for good grouping/sorting.

(cherry picked from commit 0dac63afc0)
2024-04-17 10:26:50 +02:00
Teja Mupparti a945971f48 Fix the incorrect column count after ALTER TABLE, this fixes the bug #7378 (please read the analysis in the bug for more information)
(cherry picked from commit 00068e07c5)
2024-01-24 11:48:06 -08:00
Onur Tirtir a4fe969947 Make sure to disallow creating a replicated distributed table concurrently (#7219)
See explanation in https://github.com/citusdata/citus/issues/7216.
Fixes https://github.com/citusdata/citus/issues/7216.

DESCRIPTION: Makes sure to disallow creating a replicated distributed
table concurrently

(cherry picked from commit 111b4c19bc)
2023-10-24 14:04:37 +03:00
Nils Dijk e59ffbf549
Fix leaking of memory and memory contexts in Foreign Constraint Graphs (#7236)
DESCRIPTION: Fix leaking of memory and memory contexts in Foreign
Constraint Graphs

Previously, every time we (re)created the Foreign Constraint
Relationship Graph, we created a new Memory Context while loosing a
reference to the previous context. This old context could still have
left over memory in there causing a memory leak.

With this patch we statically have one memory context that we lazily
initialize the first time we create our foreign constraint relationship
graph. On every subsequent creation, beside destroying our previous
hashmap we also reset our memory context to remove any left over
references.
2023-10-09 13:07:30 +02:00
Gürkan İndibay e5e64b7454
Adds alter database propagation - with and refresh collation (#7172)
DESCRIPTION: Adds ALTER DATABASE WITH ... and REFRESH COLLATION VERSION
support

This PR adds supports for basic ALTER DATABASE statements propagation 
support. Below statements are supported:
ALTER DATABASE <database_name> with IS_TEMPLATE <true/false>;
ALTER DATABASE <database_name> with CONNECTION LIMIT <integer_value>;
ALTER DATABASE <database_name> REFRESH COLLATION VERSION;

---------

Co-authored-by: Jelte Fennema-Nio <jelte.fennema@microsoft.com>
2023-09-12 14:09:15 +03:00
Naisila Puka 1da99f8423
PG16 - Don't propagate GRANT ROLE with INHERIT/SET option (#7190)
We currently don't support propagating these options in Citus
Relevant PG commits:
https://github.com/postgres/postgres/commit/e3ce2de
https://github.com/postgres/postgres/commit/3d14e17

Limitation:
We also need to take care of generated GRANT statements by dependencies
in attempt to distribute something else. Specifically, this part of the
code in `GenerateGrantRoleStmtsOfRole`:
```
grantRoleStmt->admin_opt = membership->admin_option;
```
In PG16, membership also has `inherit_option` and `set_option` which
need to properly be part of the `grantRoleStmt`. We can skip for now
since #7164 will take care of this soon, and also this is not an
expected use-case.
2023-09-12 12:47:37 +03:00
Naisila Puka c1dc378504
Fix WITH ADMIN FALSE propagation (#7191) 2023-09-11 15:58:24 +03:00
Onur Tirtir d628a4c21a
Add citus_schema_move() function (#7180)
Add citus_schema_move() that can be used to move tenant tables within a distributed
schema to another node. The function has two variations as simple wrappers around
citus_move_shard_placement() and citus_move_shard_placement_with_nodeid() respectively.
They pick a shard that belongs to the given tenant schema and resolve the source node
that contain the shards under given tenant schema. Hence their signatures are quite
similar to underlying functions:

```sql
-- citus_schema_move(), using target node name and node port
CREATE OR REPLACE FUNCTION pg_catalog.citus_schema_move(
	schema_id regnamespace,
	target_node_name text,
	target_node_port integer,
	shard_transfer_mode citus.shard_transfer_mode default 'auto')
RETURNS void
LANGUAGE C STRICT
AS 'MODULE_PATHNAME', $$citus_schema_move$$;

-- citus_schema_move(), using target node id
CREATE OR REPLACE FUNCTION pg_catalog.citus_schema_move(
	schema_id regnamespace,
	target_node_id integer,
	shard_transfer_mode citus.shard_transfer_mode default 'auto')
RETURNS void
LANGUAGE C STRICT
AS 'MODULE_PATHNAME', $$citus_schema_move_with_nodeid$$;
```
2023-09-08 12:03:53 +03:00
Naisila Puka 8894c76ec0
PG16 - Add rules option to CREATE COLLATION (#7185)
Relevant PG commit:
https://github.com/postgres/postgres/commit/30a53b7
30a53b7
2023-09-07 13:50:47 +03:00
Naisila Puka 5c658b4eb7
PG16 - Add citus_truncate_trigger for Citus foreign tables (#7170)
Since in PG16, truncate triggers are supported on foreign tables, we add
the citus_truncate_trigger to Citus foreign tables as well, such that the TRUNCATE
command is propagated to the table's single local shard as well.
Note that TRUNCATE command was working for foreign tables even before this
commit: see https://github.com/citusdata/citus/pull/7170#issuecomment-1706240593 for details

This commit also adds tests with user-enabled truncate triggers on Citus foreign tables:
both trigger on the shell table and on its single foreign local shard.

Relevant PG commit:
https://github.com/postgres/postgres/commit/3b00a94
2023-09-05 19:42:39 +03:00
zhjwpku 205b159606
get rid of {Push/Pop}OverrideSearchPath (#7145) 2023-09-05 17:40:22 +02:00
aykut-bozkurt 8eb3360017
Fixes visibility problems with dependency propagation (#7028)
**Problem:**
Previously we always used an outside superuser connection to overcome
permission issues for the current user while propagating dependencies.
That has mainly 2 problems:
1. Visibility issues during dependency propagation, (metadata connection
propagates some objects like a schema, and outside transaction does not
see it and tries to create it again)
2. Security issues (it is preferrable to use current user's connection
instead of extension superuser)

**Solution (high level):**
Now, we try to make a smarter decision on whether should we use an
outside superuser connection or current user's metadata connection. We
prefer using current user's connection if any of the objects, which is
already propagated in the current transaction, is a dependency for a
target object. We do that since we assume if current user has
permissions to create the dependency, then it can most probably
propagate the target as well.

Our assumption is expected to hold most of the times but it can still be
wrong. In those cases, transaction would fail and user should set the
GUC `citus.create_object_propagation` to `deferred` to work around it.

**Solution:**
1. We track all objects propagated in the current transaction (we can
handle subtransactions),
2. We propagate dependencies via the current user's metadata connection
if any dependency is created in the current transaction to address
issues listed above. Otherwise, we still use an outside superuser
connection.


DESCRIPTION: Fixes some object propagation errors seen with transaction
blocks.

Fixes https://github.com/citusdata/citus/issues/6614

---------

Co-authored-by: Nils Dijk <nils@citusdata.com>
2023-09-05 18:04:16 +03:00
Emel Şimşek a849570f3f
Improve the performance of CitusHasBeenLoaded function for a database that does not do CREATE EXTENSION citus but load citus.so. (#7123)
For a database that does not create the citus extension by running

`  CREATE EXTENSION citus;`

`CitusHasBeenLoaded ` function ends up querying the `pg_extension` table
every time it is invoked. This is not an ideal situation for a such a
database.

The idea in this PR is as follows:

### A new field in MetadataCache.
 Add a new variable `extensionCreatedState `of the following type:

```
typedef enum ExtensionCreatedState
{
        UNKNOWN = 0,
        CREATED = 1,
        NOTCREATED = 2,
} ExtensionCreatedState;
```
When the MetadataCache is invalidated, `ExtensionCreatedState` will be
set to UNKNOWN.
     
### Invalidate MetadataCache when CREATE/DROP/ALTER EXTENSION citus
commands are run.

- Register a callback function, named
`InvalidateDistRelationCacheCallback`, for relcache invalidation during
the shared library initialization for `citus.so`. This callback function
is invoked in all the backends whenever the relcache is invalidated in
one of the backends. (This could be caused many DDLs operations).

- In the cache invalidation callback,`
InvalidateDistRelationCacheCallback`, invalidate `MetadataCache` zeroing
it out.
 
- In `CitusHasBeenLoaded`, perform the costly citus is loaded check only
if the `MetadataCache` is not valid.
 
### Downsides

Any relcache invalidation (caused by various DDL operations) will case
Citus MetadataCache to get invalidated. Most of the time it will be
unnecessary. But we rely on that DDL operations on relations will not be
too frequent.
2023-09-05 13:29:35 +03:00
Hanefi Onaldi c22547d221 Create a new colocation properly after braking one
When braking a colocation, we need to create a new colocation group
record in pg_dist_colocation for the relation. It is not sufficient to
have a new colocationid value in pg_dist_partition only.

This patch also fixes a bug when deleting a colocation group if no
tables are left in it. Previously we passed a relation id as a parameter
to DeleteColocationGroupIfNoTablesBelong function, where we should have
passed a colocation id.
2023-09-05 10:58:46 +03:00
Ivan Vyazmitinov e94bf93152
#6548 2PC recovery is extremely ineffective on a cluster with multiple DATABASEs fix (#7174) 2023-09-04 15:28:22 +02:00
zhjwpku 9fd4ef042f
avoid rebuilding MetadataCache for each placement insertion (#7163) 2023-09-04 09:57:25 +02:00
zhjwpku 5034f8eba5
polish the codebase by fixing dozens of typos (#7166) 2023-09-01 12:21:53 +02:00
Gürkan İndibay b8bded6454
Adds citus_pause_node udf (#7089)
DESCRIPTION: Presenting citus_pause_node UDF enabling pausing by
node_id.

citus_pause_node takes a node_id parameter and fetches all the shards in
that node and puts AccessExclusiveLock on all the shards inside that
node. With this lock, insert is disabled, until citus_pause_node
transaction is closed.

---------

Co-authored-by: Hanefi Onaldi <Hanefi.Onaldi@microsoft.com>
2023-09-01 11:39:30 +03:00
Gürkan İndibay 4a1a5491ce
Refactors grant statements (#7153)
DESCRIPTION: Refactors all grant statements to use common code blocks to
deparse
2023-09-01 09:49:46 +03:00
zhjwpku f03291a8c8
remove useless code block (#7158) 2023-08-29 17:15:22 +02:00
Naisila Puka a17fae36b9
Disable statistics collection (#7162)
Enabled by mistake in

ba40eb363c
2023-08-29 16:09:19 +03:00
Onur Tirtir a830862717 Not undistribute Citus local table when converting it to a reference table / single-shard table 2023-08-29 12:57:28 +03:00
Onur Tirtir 34e3119b48 Intersect shard placements in a table type agnostic way
If we're in the middle of a table type conversion (such as from Citus
local table to a reference table), the table might not have all the
placements that we expect from the table type. For this reason, we
should intersect the placements of tables at hand when creating
inter-shard ddl tasks.
2023-08-29 12:57:28 +03:00
Onur Tirtir 5bdf19f517 Use CopyShardForeignConstraintCommandList in WorkerCreateShardCommandList
What we do to collect foreign key constraint commands in
WorkerCreateShardCommandList is quite similar to what we do in
CopyShardForeignConstraintCommandList. Plus, the code that we used
in WorkerCreateShardCommandList before was not able to properly handle
foreign key constraints between Citus local tables --when creating a
reference table from the referencing one.

With a few slight modifications made to
CopyShardForeignConstraintCommandList, we can use the same logic in
WorkerCreateShardCommandList too.
2023-08-29 12:57:28 +03:00
zhjwpku d97f786296
PQputCopyData's return value 0 should be considered fail (#7152) 2023-08-29 11:19:18 +02:00
Onur Tirtir d5d1684c45
Use correct errorCode for the errors thrown during recovery (#7146) 2023-08-28 11:03:38 +03:00
Gürkan İndibay 8d3a06c1c7
Adds grant/revoke privileges on database propagation (#7109)
DESCRIPTION: Adds grant/revoke propagation support for database
privileges

Following the implementation of support for granting and revoking
database privileges, certain tests that issued grants for worker nodes
experienced failures. These ones are fixed in this PR as well.
2023-08-24 14:43:19 +03:00
Naisila Puka b8c493f2c4
PG16 - Add GENERIC_PLAN option to EXPLAIN (#7141) 2023-08-23 20:15:54 +03:00
Marco Slot ba55fd67d7
Rename planner_readme.md to README.md (#7139) 2023-08-23 13:47:18 +03:00
Naisila Puka 36b51d617c
PG16 - Throw meaningful error for stats without a name on Citus tables (#7136)
Relevant PG commit:
624aa2a13b
624aa2a13bd02dd584bb0995c883b5b93b2152df
2023-08-23 10:25:01 +03:00
Gürkan İndibay 371f094b68
Removes pg_send_cancellation (#7135)
DESCRIPTION: Removes pg_send_cancellation and all references
2023-08-21 17:29:44 +03:00
zhjwpku ba2a0aec16
fix some obvious typo and reduce usage of magic number (#7130)
fix some obvious typo and reduce usage of magic number

Signed-off-by: Zhao Junwang <zhjwpku@gmail.com>
2023-08-18 14:50:20 +00:00
Naisila Puka 682dca1f12
Adds PG16Beta3 support (#6952)
DESCRIPTION: Adds PG16Beta3 support

This is the final commit that adds
PG16 compatibility with Citus's current features.

You can use Citus community with PG16Beta3. This commit:

- Enables PG16 in the configure script.
- Adds PG16 tests to CI using test images that have 16beta3
- Skips wal2json cdc test since wal2json package is not available for PG16 yet
- Fixes an isolation test

Several PG16 Compatibility commits have been merged before this final one.
All these subtasks are done https://github.com/citusdata/citus/issues/7017
See the list below:

1 - 42d956888d
Resolve compilation issues
2 - 0d503dd5ac
Ruleutils and successful CREATE EXTENSION
3 - 907d72e60d
Some test outputs
4 - 7c6b4ce103
Outer join checks, subscription password, crash fixes
5 - 6056cb2c29
get_relation_info hook to avoid crash from adjusted partitioning
6 - b36c431abb
Rework PlannedStmt and Query's Permission Info
7 - ee3153fe50
More test output fixes
8 - 2c50b5f7ff
varnullingrels additions
9 - b2291374b4
More test output fixes
10- a2315fdc67
New options to vacuum and analyze
11- 9fa72545e2
Fix AM dependency and grant's admin option
12- 2d6cf8e79a
One more outer join check

Stay tuned for PG16 new features in Citus :)
2023-08-17 21:02:59 +03:00
Naisila Puka 2d6cf8e79a
PG16 compatibility - one more outer join check (#7126)
PG16 compatibility - part 11

Check out part 1 42d956888d
part 2 0d503dd5ac
part 3 907d72e60d
part 4 7c6b4ce103
part 5 6056cb2c29
part 6 b36c431abb
part 7 ee3153fe50
part 8 2c50b5f7ff
part 9 b2291374b4
part 10 a2315fdc67
part 11 9fa72545e2

This commit is in the series of PG16 compatibility commits.
We already took care of the majority of necessary outer join checks
in part 4 7c6b4ce103
However, In RelationInfoContainsOnlyRecurringTuples,
we need to add one more check of whether we are dealing
with an outer join RTE using IsRelOptOuterJoin function.
This prevents an outer join crash in sqlancer_failures.sql test.

We expect one more commit of PG compatibility with Citus's current
features are regression tests sanity.
2023-08-17 19:07:18 +03:00
zhjwpku b10320be6f
fix wrong type convertion (#7116)
partitionMethod and replicationModel are both type char, there seems
meaningless to convert them to type Oid implicitly.
2023-08-17 13:53:43 +02:00
Naisila Puka 9fa72545e2
PG16 compatibility - fix AM dependency and grant's admin option (#7113)
PG16 compatibility - part 11

Check out part 1 42d956888d
part 2 0d503dd5ac
part 3 907d72e60d
part 4 7c6b4ce103
part 5 6056cb2c29
part 6 b36c431abb
part 7 ee3153fe50
part 8 2c50b5f7ff
part 9 b2291374b4
part 10 a2315fdc67

This commit is in the series of PG16 compatibility commits. It fixes
AM dependency and grant's admin option:

- Fix with admin option in grants 
grantstmt->admin_opt no longer exists in PG16
instead, grantstmt has a list of options, one of them is admin option.
Relevant PG commit:
e3ce2de09d
e3ce2de09d814f8770b2e3b3c152b7671bcdb83f

- Fix pg_depend entry to AMs after ALTER TABLE .. SET ACCESS METHOD 
Relevant PG commit:
97d8910104
97d89101045fac8cb36f4ef6c08526ea0841a596


More PG16 compatibility commits are coming soon:
We are very close to merging "PG16Beta3 Support - Regression tests sanity"
2023-08-17 11:22:34 +03:00
Naisila Puka 71c475af52
Fix GetUndistributableDependency (#7124)
This is a leftover task from merging enterprise to community.
Roles are distributed in community now, the comment is stale and the
check is redundant.
2023-08-17 10:57:22 +03:00
Naisila Puka a2315fdc67
PG16 compatibility - new options to vacuum and analyze (#7114)
PG16 compatibility - part 10

Check out part 1 42d956888d
part 2 0d503dd5ac
part 3 907d72e60d
part 4 7c6b4ce103
part 5 6056cb2c29
part 6 b36c431abb 
part 7 ee3153fe50
part 8 2c50b5f7ff
part 9 b2291374b4

This commit is in the series of PG16 compatibility commits. It:

- Adds buffer_usage_limit to vacuum and analyze
- Adds process_main, skip_database_stats, only_database_stats to vacuum

Important Note: adding these options is actually required for check-vanilla tests to succeed.
However, in concept, this PR belongs to "PG16 new features",
rather than "PG16 regression tests sanity"

Relevant PG commits:
1cbbee0338
1cbbee03385763b066ae3961fc61f2cd01a0d0d7
4211fbd841
4211fbd8413b26e0abedbe4338aa7cda2cd469b4
a46a7011b2
a46a7011b27188af526047a111969f257aaf4db8

More PG16 compatibility commits are coming soon ...
2023-08-16 16:18:28 +03:00
Naisila Puka b982f2dee6
Changes PROCESS_TOAST default value to true (#7122)
Process toast should be true by default, like in PG.
2023-08-16 14:40:24 +03:00
Naisila Puka 2c50b5f7ff
PG16 compatibility - varnullingrels additions (#7107)
PG16 compatibility - part 7

Check out part 1 42d956888d
part 2 0d503dd5ac
part 3 907d72e60d
part 4 7c6b4ce103
part 5 6056cb2c29
part 6 b36c431abb
part 7 ee3153fe50

This commit is in the series of PG16 compatibility commits. PG16 introduced a new entry
varnnullingrels to Var, which represents our partkey in pg_dist_partition.
This commit does the necessary changes in Citus to support this.
Relevant PG commit:
2489d76c49
2489d76c4906f4461a364ca8ad7e0751ead8aa0d

More PG16 compatibility commits are coming soon ...
2023-08-15 13:07:55 +03:00
Naisila Puka b36c431abb
PG16 compatibility - Rework PlannedStmt and Query's Permission Info (#7098)
PG16 compatibility - Part 6

Check out part 1 42d956888d
part 2 0d503dd5ac
part 3 907d72e60d
part 4 7c6b4ce103
part 5 6056cb2c29

This commit is in the series of PG16 compatibility commits.
It handles the Permission Info changes in PG16. See below:

The main issue lies in the following entries of PlannedStmt: {
   rtable
   permInfos
}

Each rtable has an int perminfoindex, and its actual permission info is
obtained through the following:
permInfos[perminfoindex]
We had crashes because perminfoindexes were not updated in the finalized
planned statement after distributed planner hook.
So, basically, everywhere we set a query's or planned statement's rtable
entry, we need to set the rteperminfos/permInfos accordingly.

Relevant PG commits:
a61b1f7482
a61b1f74823c9c4f79c95226a461f1e7a367764b
b803b7d132
b803b7d132e3505ab77c29acf91f3d1caa298f95

More PG16 compatibility commits are coming soon ...
2023-08-09 15:23:00 +03:00
Naisila Puka 6056cb2c29
PG16 compatibility - get_relation_info hook to avoid crash from adjusted partitioning (#7099)
PG16 compatibility - Part 5

Check out part 1 42d956888d
part 2 0d503dd5ac
part 3 907d72e60d
part 4 7c6b4ce103

This commit is in the series of PG16 compatibility commits. Find the explanation below:

If we allow to adjust partitioning, we get a crash when accessing
amcostestimate of partitioned indexes, because amcostestimate is NULL
for them. The following PG commit is the culprit:
3c569049b7
3c569049b7b502bb4952483d19ce622ff0af5fd6
Previously, partitioned indexes would just be ignored.
Now, they are added in the list. However get_relation_info expects the
tables which have partitioned indexes to have the inh flag set properly.
AdjustPartitioningForDistributedPlanning plays with that flag, hence we
don't get the desired behaviour.
The hook is simply removing all partitioned indexes from the list.

More PG16 compatibility commits are coming soon ...
2023-08-08 15:51:21 +03:00
Naisila Puka 7c6b4ce103
PG16 compatibility - outer join checks, subscription password, crash fixes (#7097)
PG16 compatibility - Part 4

Check out part 1 42d956888d
part 2 0d503dd5ac
part 3 907d72e60d

This commit is in the series of PG16 compatibility commits.
It adds some outer join checks to the planner,
the new password_required option to the subscription,
and a crash fix related to PGIOAlignedBlock, see below for more details:

- Fix PGIOAlignedBlock Assert crash in PG16 
Relevant PG commit:
faeedbcefd
faeedbcefd40bfdf314e048c425b6d9208896d90

- Pass planner info as argument to make_simple_restrictinfo 
Pre PG16 passing plannerInfo to make_simple_restrictinfo
was only needed for placeholder Vars, which is not the case
in this part of the codebase because we are building the
expression from shard intervals which don't have placeholder
vars.
However, PG16 is counting baserels appearing in clause_relids
and is deleting the rels mentioned in plannerinfo->outer_join_rels
Hence directly accessing plannerinfo.
We will crash if we leave it as NULL.
For reference
2489d76c49 (diff-e045c41eda9686451a7993e91518e40056b3739365e39eb1b70ae438dc1f7c76R207)
Relevant PG commit:
2489d76c49
2489d76c4906f4461a364ca8ad7e0751ead8aa0d

- Add outer join checks, root->simple_rel_array

- fix rebalancer to include passwork_required option 
Relevant PG commit:
c3afe8cf5a
c3afe8cf5a1e465bd71e48e4bc717f5bfdc7a7d6

More PG16 compatibility commits are coming soon ...
2023-08-04 14:51:28 +03:00
Önder Kalacı 4ae3982d14
Add single-shard router Merge command support (#7088)
Similar to https://github.com/citusdata/citus/pull/7077.

As PG 16+ has changed the join restriction information for certain outer
joins, MERGE is also impacted given that is is also underlying an outer
join.

See #7077 for the details.
2023-08-04 08:16:29 +03:00
Naisila Puka 0d503dd5ac
PG16 compatibility: ruleutils and successful CREATE EXTENSION (#7087)
PG16 compatibility - Part 2

Part 1 provided successful compilation against pg16beta2.
42d956888d

This PR provides ruleutils changes with pg16beta2 and successful CREATE EXTENSION command.
Note that more changes are needed in order to have successful regression tests.
More commits are coming soon ...

For any_value changes, I referred to this commit
8ef94dc1f5
where we did something similar for PG14 support.
2023-08-02 16:04:51 +03:00
Önder Kalacı 960a5f6104
Improve failure handling of distributed execution (#7090)
Prior to this commit, the code would skip processing the
errors happened for local commands.

Prior to https://github.com/citusdata/citus/pull/5379, it might
make sense to allow the execution continue. But, as of today,
if a modification fails on any placement, we can safely fail
the execution.

The first commit show the problem in action. The second commit
includes the fix and the test fixes.
2023-08-01 16:47:59 +03:00
Onur Tirtir dd6ea1ebd5
Makes sure to handle NULL constraints for ADD COLUMN commands (#7093)
DESCRIPTION: Fixes a bug that causes an unexpected error when adding a
column with a NULL constraint

Fixes https://github.com/citusdata/citus/issues/7092.
2023-08-01 11:07:47 +03:00
Önder Kalacı cb5eb73048
Add support for router INSERT .. SELECT commands (#7077)
Tradionally our planner works in the following order:
   router - > pushdown -> repartition -> pull to coordinator

However, for INSERT .. SELECT commands, we did not support "router".

In practice, that is not a big issue, because pushdown planning can
handle router case as well.

However, with PG 16, certain outer joins are converted to JOIN without
any conditions (e.g., JOIN .. ON (true)) and the filters are pushed down
to the tables.

When the filters are pushed down to the tables, router planner can
detect. However, pushdown planner relies on JOIN conditions.

An example query:
```
INSERT INTO agg_events (user_id)
        SELECT raw_events_first.user_id
        FROM raw_events_first LEFT JOIN raw_events_second
        	ON raw_events_first.user_id = raw_events_second.user_id
        WHERE raw_events_first.user_id = 10;
```

As a side effect of this change, now we can also relax certain
limitation that "pushdown" planner emposes, but not "router". So, with
this PR, we also allow those.

Closes https://github.com/citusdata/citus/pull/6772
DESCRIPTION: Prevents unnecessarily pulling the data into coordinator
for some INSERT .. SELECT queries that target a single-shard group
2023-07-28 15:07:20 +03:00