Commit Graph

43 Commits (90dde46f3380d2a8caa248f335f1800c6900aee3)

Author SHA1 Message Date
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
Teja Mupparti ca65d2ba0b Fix flaky tests local_shards_execution and local_shards_execution_replication.
O Simple fix is to add ORDER BY to have definitive results.
O Add search_path explicitly after reconnecting, this avoids creating objects in public schema
  which prevents us from repetitive running of tests.
O multi_mx_modification is not designed to run repetitive, so isolate it.
2023-02-15 09:18:10 -08:00
Naisila Puka 35b4ddc355
Pg15 support (#6085)
* Adjust configure script to allow PG15

* Adds copy of ruleutils_14.c as ruleutils_15.c

* Uses get_namespace_name_or_temp in ruleutils_15.c

Relevant PG commit:
48c5c9068211e0a04fd9553c8714b2821ed3ad17

* Clean up code using "(expr) ? true : false" in ruleutils_15.c

Relevant PG commit:
fd0625c7a9c679c0c1e896014b8f49a489c3a245

* Change varno from Index (unsigned int) to int in ruleutils_15.c

Relevant PG commit:
e3ec3c00d85bd2844ffddee83df2bd67c4f8297f

* Adds find_recursive_union to ruleutils_15.c

Relevant PG commit:
3f50b82639637c9908afa2087de7588450aa866b

* Fix display of SQL-std func's args in INSERT/SELECT in ruleutils_15.c

Relevant PG commit:
a8d8445a7b2f80f6d0bfe97b19f90bd2cbef8759

* Fix ruleutils_15.c's dumping of whole-row Vars in more contexts

Relevant PG commit:
43c2175121c829c8591fc5117b725f1f22bfb670

* Fix assorted missing logic for GroupingFunc nodes in ruleutils_15.c

Relevant PG commit:
2591ee8ec44d8cbc8e1226550337a64c684746e4

* Adds grammar support for SQL/JSON clauses in ruleutils_15.c

Relevant PG commit:
f79b803dcc98d707450e158db3638dc67ff8380b

* Adds SQL/JSON constructors to ruleutils_15.c

Relevant PG commits:
f4fb45d15c59d7add2e1b81a9d477d0119a9691a
cc7401d5ca498a84d9b47fd2e01cebd8e830e558

* Adds support for MERGE in ruleutils_15.c

Relevant PG commit:
7103ebb7aae8ab8076b7e85f335ceb8fe799097c

* Add IS JSON predicate to ruleutils_15.c

Relevant PG commit:
33a377608fc29cdd1f6b63be561eab0aee5c81f0

* Add SQL/JSON query functions to ruleutils_15.c

Relevant PG commit:
1a36bc9dba8eae90963a586d37b6457b32b2fed4

* Adds three different SQL/JSON values to ruleutils_15.c

Relevant PG commits:
606948b058dc16bce494270eea577011a602810e
49082c2cc3d8167cca70cfe697afb064710828ca

* Adds JSON table functions in ruleutils_15.c

Relevant PG commit:
4e34747c88a03ede6e9d731727815e37273d4bc9

* Add PLAN function for JSON table in ruleutils_15.c

Relevant PG commit:
fadb48b00e02ccfd152baa80942de30205ab3c4f

* Remove extra blank lines before block-closing braces ruleutils_15.c

Relevant PG commit:
24d2b2680a8d0e01b30ce8a41c4eb3b47aca5031

* set_deparse_plan: Reuse variable to appease Coverity ruleutils_15.c

Relevant PG commit:
e70813fbc4aaca35ec012d5a426706bd54e4acab

* Mechanical code beautification ruleutils_15.c

Relevant PG commit:
23e7b38bfe396f919fdb66057174d29e17086418

* Rename value_type to item_type in ruleutils_15.c

Relevant PG commit:
3ab9a63cb638a1fd99475668e2da9c237495aeda

* Show 'AS "?column?"' explicitly when it's important in ruleutils_15.c

Relevant PG commit:
c7461fc25558832dd347a9c8150b0f1ed85e36e8

* Fix ruleutils_15.c issues with dropped cols in funcs-returning-composite

Relevant PG commit:
c1d1e8469c77ce6b8e5310955580b4a3eee7fe96

* Change comment regarding functions returning composite in ruleutils_15.c

Relevant PG commit:
c2fa113ddb1117b1f03e91960f65d5d7d8a90270

* Replace int nodes with bool nodes where needed

In PG15, Boolean nodes are added. Pre PG15, internal Boolean values
in Create Role commands were represented by Integer nodes. This
commit replaces int nodes logic with bool nodes logic where needed.
Mostly there are CREATE ROLE logic changes.

Relevant PG commit:
941460fcf731a32e6a90691508d5cfa3d1f8eeaf

* Handle new option colliculocale in CREATE COLLATION logic

In PG15, there is an added option to use ICU as global locale provider.
pg_collation has three locale-related fields: collcollate and collctype,
which are libc-related fields, and a new one colliculocale, which is the
ICU-related field. Only the libc-related fields or the ICU-related field
is set, never both.

Relevant PG commits:
f2553d43060edb210b36c63187d52a632448e1d2
54637508f87bd5f07fb9406bac6b08240283be3b

* Add PG15 tests to CI using test images that have 15beta2 (#6093)

* Change warning message in pg_signal_backend()

Relevant PG commit:
7fa945b857cc1b2964799411f1633468826861ff

* Revert "Add missing ifdef for PG 15"

This reverts commit c7b51025ab.

* Fixes tests for ALTER TRIGGER RENAME consistency for part. tables

Relevant PG commit:
80ba4bb383538a2ee846fece6a7b8da9518b6866

* Prevent creating child triggers on partitions when adding new node

Pre PG15, tgisinternal is true for a "child" trigger on a partition
cloned from the trigger on the parent.
In PG15, tgisinternal is false in that case. However, we don't want to
create this trigger on the partition since it will create a conflict
when we try to attach the partition to the parent table:
ERROR: trigger "..." for relation "{partition_name}" already exists

Relevant PG commit:
f4566345cf40b068368cb5617e61318da60676ec

* Fix tests for generated columns dependency changes

In PG15, For GENERATED columns, all dependencies of the generation
expression are recorded as NORMAL dependencies of the column itself.
This requires CASCADE to drop generated cols with the original col.
PRE PG15, dependencies were recorded as AUTO, with which
generated columns are silently dropped with the original column.

Relevant PG commit:
cb02fcb4c95bae08adaca1202c2081cfc81a28b5

* Explicitly cast catalog "char" column to text before concatenation

Relevant PG commit:
07eee5a0dc642d26f44d65c4e6263304208e8583

* Remove 'AS "?column?"' from test outputs

There were some instances in the following tst outputs
in planning debug outputs where AS "?column?" is added.
We add a normalization rule to remove it as it is not
important.

cte_inline.out
recursive_relation_planning_restriction_pushdown.out

Relevant PG commit:
c7461fc25558832dd347a9c8150b0f1ed85e36e8

* Use pg_backup_stop(PG15) instead of pg_stop_backup(PG<15)

Add an alternative test output because of the change in the
backup modes of Postgres. Specifically here, there is a renaming
issue: pg_stop_backup PRE PG15 vs pg_backup_stop PG15+
The alternative output can be deleted when we drop support for PG14

Relevant PG commit:
39969e2a1e4d7f5a37f3ef37d53bbfe171e7d77a

* Adds citus.mitmfifo GUC

Previously we setting this configuration parameter
in the fly for failure tests schedule.
However, PG15 doesn't allow that anymore: reserved prefixes
like "citus" cannot be used to set non-existing GUCs.

Relevant PG commit:
88103567cb8fa5be46dc9fac3e3b8774951a2be7

* Handles EXPLAIN output diffs in PG15 - Extra result lines

To handle extra "Result" lines in explain outputs, we add explain
method to multi_test_helpers.sql file
- plan_without_result_lines() is added for cases where we want the
whole explain output with only "Result" lines removed

* Handles EXPLAIN output diffs in PG15, Hash Agg/Join leverage

To handle differences in usage of GroupAggregate vs HashAggregate
or Merge Join vs Hash join in cases where this detail doesn't
seem to matter, we use coordinator_plan().
- coordinator_plan() is updated to remove "Result" lines

There are some cases where we have subplans so we add a new
function that prints all Task Count lines as well
- coordinator_plan_with_subplans()

Still not sure of the relevant PG commit
Could be db0d67db2401eb6238ccc04c6407a4fd4f985832
but disabling enable_group_by_reordering didn't help.

* Handles EXPLAIN output diffs in PG15: enable_group_by_reordering

Relevant PG commit
db0d67db2401eb6238ccc04c6407a4fd4f985832

* Normalizes Memory Usage, Buckets, Batches for PG15 explain diffs

We create a new function in multi_test_helpers, which is similar
to explain_merge function in PG15. This explain helper function
normalies Memory Usage, Buckets and Batches, and we use it in the
tests which give a different output for PG15.

* Bump test images to 15beta3 (#6172)

* Omit namespace in post-copy errmsg

Relevant PG commit:
069d33d0c5a021601245e44df77a0423ddd69359

* Handles EXPLAIN output diffs in PG15: extra arrows&result lines

To handle extra "->" arrows resulting from extra Result lines
in explain outputs, we add the following explain method to
multi_test_helpers.sql file

- plan_without_arrows() is added for cases where we want the
whole explain output without arrows and without Result lines

* Alters public schema's owner to pg_database_owner in PG15

In PG15, public schema is owned by pg_database_owner role.
In multi_extension, we drop and recreate the ppublic schema,
hence its owner become the default user in our tests, postgres.
Change that to pg_database_owner for PG15 consistency.

This results in alternative test output for public schema grants
in the following test:

grant_on_schema_propagation.sql

Relevant PG commit: b073c3ccd06e4cb845e121387a43faa8c68a7b62

* Add alternative test outputs for change in Insert Select display

citus_local_tables_queries.sql
coordinator_shouldhaveshards.sql
cte_inline.sql
insert_select_repartition.sql
intermediate_result_pruning.sql
local_shard_execution.sql
local_shard_execution_replicated.sql
multi_deparse_shard_query.sql
multi_insert_select.sql
multi_insert_select_conflict.sql
multi_mx_insert_select_repartition.sql
mx_coordinator_shouldhaveshards.sql
single_node.sql

Relevant PG commit:
a8d8445a7b2f80f6d0bfe97b19f90bd2cbef8759

* Fixes columnar tap tests for PG15

In PG15, Perl test modules have been moved to a new namespace.
Also, postgres node new() and get_new_node() methods have been
unified to one method: new()

We create separate tap tests for PG13/14 and PG15+
and update the Makefiles accordingly.

Relevant PG commits:
201a76183e2056c2217129e12d68c25ec9c559c8
b3b4d8e68ae83f432f43f035c7eb481ef93e1583

* Handles EXPLAIN output diffs in PG15: HashAgg Leverage,alt. output

Still not sure of the relevant PG commit
Could be db0d67db2401eb6238ccc04c6407a4fd4f985832
but disabling enable_group_by_reordering didn't help.
2022-08-24 17:59:17 +02:00
Marco Slot e683993449 Fix prepared statement bug when switching from local to remote execution 2022-05-20 18:55:43 +02:00
Burak Velioglu 1460452442 Introduce CREATE/DROP VIEW
Adds support for propagating create/drop view commands and views to
worker node while scaling out the cluster. Since views are dropped while
converting the table type, metadata connection will be used while
propagating view commands to not switch to sequential mode.
2022-05-10 13:07:14 +03:00
Onder Kalaci a2debe0f02 Do not assign distributed transaction ids for local execution
In the past, for all modifications on the local execution,
we enabled 2PC (with 6a7ed7b309).

This also required us to enable coordinated transactions
via https://github.com/citusdata/citus/pull/4831 .

However, it does have a very substantial impact on the
distributed deadlock detection. The distributed deadlock
detection is designed to avoid single-statement transactions
because they cannot lead to any actual deadlocks.

The implementation is to skip backends without distributed
transactions are assigned. Now that we assign single
statement local executions in the lock graphs, we are
conflicting with the design of distributed deadlock
detection.

In general, we should fix it. However, one might
think that it is not a big deal, even if the processes
show up in the lock graphs, the deadlock detection
should not be causing any false positives. That is
false, unless https://github.com/citusdata/citus/issues/1803
is fixed. Now that local processes are considered as a single
distributed backend, the lock graphs might find:

    local execution 1 [tx id: 1] -> any local process [tx id: 0]
    any local process [tx id: 0] -> local execution 2 [tx id: 2]

And, decides that there is a distributed deadlock.

This commit is:
   (a) right thing to do, as local execuion should not need any
       distributed tx id
   (b) Eliminates performance issues that might come up with
       deadlock detection does a lot of unncessary checks
   (c) After moving local execution after the remote execution
       via https://github.com/citusdata/citus/pull/4301, the
       vauge requirement for assigning distributed tx ids are
       already gone.
2022-04-13 13:25:12 +02:00
Marco Slot 490765a754 Enable re-partition joins after local execution 2022-02-23 19:40:21 +01:00
Burak Velioglu fa6866ed36
Start to propagate functions to worker nodes with
CREATE FUNCTION command together with it's dependencies.

If the function depends on any nondistributable object,
function will be created only locally. Parameterless
version of create_distributed_function becomes obsolete
with this change, it will deprecated from the code with a subsequent PR.
2022-02-18 13:56:51 +03:00
Burak Velioglu ed8e32de5e
Sync pg_dist_object on an update and propagate while syncing to a new node
Before that PR we were updating citus.pg_dist_object metadata, which keeps
the metadata related to objects on Citus, only on the coordinator node. In
order to allow using those object from worker nodes (or erroring out with
proper error message) we've started to propagate that metedata to worker
nodes as well.
2021-12-06 19:25:50 +03:00
Jelte Fennema bb5c494104 Enable binary encoding by default on PG14
Since PG14 we can now use binary encoding for arrays and composite types
that contain user defined types. This was fixed in this commit in
Postgres: 670c0a1d47

This change starts using that knowledge, by not necessarily falling back
to text encoding anymore for those types.

While doing this and testing a bit more I found various cases where
binary encoding would fail that our checks didn't cover. This fixes
those cases and adds tests for those. It also fixes EXPLAIN ANALYZE
never using binary encoding, which was a leftover of workaround that
was not necessary anymore.

Finally, it changes the default for both `citus.enable_binary_protocol`
and `citus.binary_worker_copy_format` to `true` for PG14 and up. In our
cloud offering `binary_worker_copy_format` already was true by default.
`enable_binary_protocol` had some bug with MX and user defined types,
this bug was fixed by the above mentioned fixes.
2021-09-06 10:27:29 +02:00
Onder Kalaci 76ae5dd0db Improve regression tests for prepared statements
With a recent commit, we made (644b266dee)
the behaviour of prepared statements for local cached plans has
slightly changed.

Now, Citus caches the plans when they are re-used. This make triggering
of local cached plans on the 7th execution, and 8th execution is the
first time the plan is used from the cached.

So, the tests are improved to cover 8th execution.
2021-06-21 13:34:44 +03:00
Hanefi Onaldi 878513f325
Remove all occurences of replication_model GUC 2021-05-21 16:14:59 +03:00
Nils Dijk c91f8d8a15
Feature: localhost guc (#4836)
DESCRIPTION: introduce `citus.local_hostname` GUC for connections to the current node

Citus once in a while needs to connect to itself for some systems operations. This used to be hardcoded to `localhost`. The hardcoded hostname causes some issues, for example in environments where `sslmode=verify-full` is required. It is not always desirable or even feasible to get `localhost` as an alt name on the certificate.

By introducing a GUC to use when connecting to the current instance the user has more control what network path is used and what hostname is required to be present in the server certificate.
2021-05-12 16:59:44 +02:00
Marco Slot 5de3337b2f Support local execution for INSERT..SELECT with re-partitioning 2021-01-06 16:15:53 +01:00
Onder Kalaci f7e1aa3f22 Multi-row INSERTs use local execution when placements are local
Multi-row execution already uses sequential execution. When shards
are local, using local execution is profitable as it avoids
an extra connection establishment to the local node.
2020-12-01 21:37:59 +03:00
SaitTalhaNisanci 0f209377c4
Fix incorrect join related fields (#4242)
* Fix incorrect join related fields

Ruleutils expect to give the original index of join columns hence we
should consider the dropped columns while setting the fields in
SetJoinRelatedFieldsCompat.

* add some more tests for joins

* Move tests to join.sql and create a utility function
2020-10-19 18:28:39 +03:00
Sait Talha Nisanci 4308d867d9 remove task-tracker in comments, documentation 2020-07-21 16:21:01 +03:00
Jelte Fennema 0259815d3a
Fix EXPLAIN ANALYZE received data counter issues (#3917)
In #3901 the "Data received from worker(s)" sections were added to EXPLAIN
ANALYZE. After merging @pykello posted some review comments. This addresses
those comments as well as fixing a other issues that I found while addressing 
them. The things this does:

1. Fix `EXPLAIN ANALYZE EXECUTE p1` to not increase received data on every
   execution
2. Fix `EXPLAIN ANALYZE EXECUTE p1(1)` to not return 0 bytes as received data
   allways.
3. Move `EXPLAIN ANALYZE` specific logic to `multi_explain.c` from
   `adaptive_executor.c`
4. Change naming of new explain sections to `Tuple data received from node(s)`.
   Firstly because a task can reference the coordinator too, so "worker(s)" was
   incorrect. Secondly to indicate that this is tuple data and not all network
   traffic that was performed.
5. Rename `totalReceivedData` in our codebase to `totalReceivedTupleData` to
   make it clearer that it's a tuple data counter, not all network traffic.
6. Actually add `binary_protocol` test to `multi_schedule` (woops)
7. Fix a randomly failing test in `local_shard_execution.sql`.
2020-06-17 11:33:38 +02:00
Jelte Fennema 927de6d187
Show amount of data received in EXPLAIN ANALYZE (#3901)
Sadly this does not actually work yet for binary protocol data, because
when doing EXPLAIN ANALYZE we send two commands at the same time. This
means we cannot use `SendRemoteCommandParams`, and thus cannot use the
binary protocol. This can still be useful though when using the text
protocol, to find out that a lot of data is being sent.
2020-06-15 16:01:05 +02:00
Hadi Moshayedi 7c52c6edb0 CTE statistics in EXPLAIN ANALYZE 2020-06-11 02:39:59 -07:00
Onder Kalaci 891d99efaf add order by to some tests to make the output consistent 2020-05-01 12:41:51 +02:00
Onder Kalaci 0cb7ab2d05 Explicitly mark queries in physical planner for [not] having parameters
Physical planner doesn't support parameters. If the parameters have already
been resolved when the physical planner handling the queries, mark it.
The reason is that the executor is unaware of this, and sends the parameters
along with the worker queries, which fails for composite types.

(See `DissuadePlannerFromUsingPlan()` for the details of paramater resolving)
2020-04-24 12:49:43 +02:00
SaitTalhaNisanci 233e4a24d1
use local execution within transaction block (#3714)
* use local executon when in a transaction block

When we are inside a transaction block, there could be other methods
that need local execution, therefore we will use local execution in a
transaction block.

* update test outputs with transaction block local execution

* add a test to verify we dont leak intermediate schemas
2020-04-09 12:41:58 +03:00
SaitTalhaNisanci 9d2f3c392a enable local execution in INSERT..SELECT and add more tests
We can use local copy in INSERT..SELECT, so the check that disables
local execution is removed.

Also a test for local copy where the data size >
LOCAL_COPY_FLUSH_THRESHOLD is added.

use local execution with insert..select
2020-03-18 09:34:39 +03:00
SaitTalhaNisanci 39bbec0f30 add tests for local copy execution 2020-03-18 09:28:59 +03:00
Onur Tirtir a14739f808
Local execution of ddl/drop/truncate commands (#3514)
* reimplement ExecuteUtilityTaskListWithoutResults for local utility command execution

* introduce new functions for local execution of utility commands

* change ErrorIfTransactionAccessedPlacementsLocally logic for local utility command execution

* enable local execution for TRUNCATE command on distributed & reference tables

* update existing tests for local utility command execution

* enable local execution for DDL commands on distributed & reference tables

* enable local execution for DROP command on distributed & reference tables

* add normalization rules for cascaded commands

* add new tests for local utility command execution
2020-03-13 15:39:32 +03:00
Hanefi Onaldi c0ad44f975
Fix early exit bug on intermediate result pruning
There are 2 problems with our early exit strategy that this commit fixes:

1- When we decide that a subplan results are sent to all worker nodes,
we used to skip traversing the whole distributed plan, instead of
skipping only the subplan.

2- We used to consider all available nodes in the cluster (secondaries
and inactive nodes as well as active primaries) when deciding on early
exit strategy. This resulted in failures to early exit when there are
secondaries or inactive nodes.
2020-03-05 16:41:44 +03:00
Onder Kalaci f72916875f Expand test coverage for combinations of master evalution, deferred pruning, parameters, local execution
- Router           & Remote & Requires Master Evaluation & With Param & Without Param
- Fast Path Router & Remote & Requires Master Evaluation & With Param & Without Param
2020-03-05 12:37:22 +01:00
Onder Kalaci fd17e4578e Improve tests 2020-01-17 16:02:57 +01:00
Onder Kalaci 0bf1e81e33 Cache local plans on BeginScan 2020-01-17 16:02:57 +01:00
Jelte Fennema 246435be7e
Lazy query deparsing executable queries (#3350)
Deparsing and parsing a query can be heavy on CPU. When locally executing 
the query we don't need to do this in theory most of the time.

This PR is the first step in allowing to skip deparsing and parsing
the query in these cases, by lazily creating the query string and
storing the query in the task. Future commits will make use of this and
not deparse and parse the query anymore, but use the one from the task
directly.
2020-01-17 11:49:43 +01:00
Marco Slot 06709ee108 Always use NOTICE in log_remote_commands and avoid redaction when possible 2020-01-13 18:24:36 +01:00
Önder Kalacı a174eb4f7b
Do not go through standard_planner() for INSERTs (#3348)
That seems unnecessary. We already have the notion of FastPath queries,
simply add it there.
2020-01-03 12:15:22 +00:00
Jelte Fennema 5fee9d04c9 Uncomment local execution EXPLAIN ANALYZE tests 2020-01-02 18:56:32 +00:00
Philip Dubé c563e0825c Strip trailing whitespace and add final newline (#3186)
This brings files in line with our editorconfig file
2019-11-21 14:25:37 +01:00
Önder Kalacı 0b3d4e55d9
Local execution should not change hasReturning for distributed tables (#3160)
It looks like the logic to prevent RETURNING in reference tables to
have duplicate entries that comes from local and remote executions
leads to missing some tuples for distributed tables.

With this PR, we're ensuring to kick in the logic for reference tables
only.
2019-11-08 12:49:56 +01:00
SaitTalhaNisanci 29d45bd1b9
Do not assign InvalidOid for local execution while extracting parameters (#3131)
* do not assign InvalidOid for local execution while extracting parameters

* rename functions

* rename parameter and replace function
2019-10-28 14:28:22 +03:00
Önder Kalacı dceaddbe4d
Remove real-time/router executors (step 1) (#3125)
See #3125 for details on each item.

* Remove real-time/router executor tests-1

These are the ones which doesn't have '_%d' in the test
output files.

* Remove real-time/router executor tests-2

These are the ones which has in the test
output files.

* Move the tests outputs to correct place

* Make sure that single shard commits use 2PC on adaptive executor

It looks like we've messed the tests in #2891. Fixing back.

* Use adaptive executor for all router queries

This becomes important because when task-tracker is picked, we
used to pick router executor, which doesn't make sense.

* Remove explicit references to real-time/router executors in the tests

* JobExecutorType never picks real-time/router executors

* Make sure to go incremental in test output numbers

* Even users cannot pick real-time anymore

* Do not use real-time/router custom scans

* Get rid of unnecessary normalizations

* Reflect unneeded normalizations

* Get rid of unnecessary test output file
2019-10-25 10:54:54 +02:00
Onder Kalaci 219f3676a0 Improve some tests around local execution and CTE inlining on pg 12 2019-09-25 10:53:19 +02:00
Hadi Moshayedi 48078a30e6 Fix wait_until_metadata_sync() for postgres 12.
Postgres 12 now has an assertion that the calls to WaitLatchOrSocket
handle postmaster death.
2019-09-23 14:15:35 -07:00
Philip Dubé 06faba91c0 Include ifdefs for pg12 API changes, update local_shard_executiuon test to avoid CTE inlining 2019-09-23 20:22:35 +00:00
Jelte Fennema e4cfea3751 Correctly add schema when distributing sequence definitons
Fixes 2958
2019-09-13 17:19:35 +02:00
Onder Kalaci 0b0c779c77 Introduce the concept of Local Execution
/*
 * local_executor.c
 *
 * The scope of the local execution is locally executing the queries on the
 * shards. In other words, local execution does not deal with any local tables
 * that are not shards on the node that the query is being executed. In that sense,
 * the local executor is only triggered if the node has both the metadata and the
 * shards (e.g., only Citus MX worker nodes).
 *
 * The goal of the local execution is to skip the unnecessary network round-trip
 * happening on the node itself. Instead, identify the locally executable tasks and
 * simply call PostgreSQL's planner and executor.
 *
 * The local executor is an extension of the adaptive executor. So, the executor uses
 * adaptive executor's custom scan nodes.
 *
 * One thing to note that Citus MX is only supported with replication factor = 1, so
 * keep that in mind while continuing the comments below.
 *
 * On the high level, there are 3 slightly different ways of utilizing local execution:
 *
 * (1) Execution of local single shard queries of a distributed table
 *
 *      This is the simplest case. The executor kicks at the start of the adaptive
 *      executor, and since the query is only a single task the execution finishes
 *      without going to the network at all.
 *
 *      Even if there is a transaction block (or recursively planned CTEs), as long
 *      as the queries hit the shards on the same, the local execution will kick in.
 *
 * (2) Execution of local single queries and remote multi-shard queries
 *
 *      The rule is simple. If a transaction block starts with a local query execution,
 *      all the other queries in the same transaction block that touch any local shard
 *      have to use the local execution. Although this sounds restrictive, we prefer to
 *      implement in this way, otherwise we'd end-up with as complex scenarious as we
 *      have in the connection managements due to foreign keys.
 *
 *      See the following example:
 *      BEGIN;
 *          -- assume that the query is executed locally
 *          SELECT count(*) FROM test WHERE key = 1;
 *
 *          -- at this point, all the shards that reside on the
 *          -- node is executed locally one-by-one. After those finishes
 *          -- the remaining tasks are handled by adaptive executor
 *          SELECT count(*) FROM test;
 *
 *
 * (3) Modifications of reference tables
 *
 *		Modifications to reference tables have to be executed on all nodes. So, after the
 *		local execution, the adaptive executor keeps continuing the execution on the other
 *		nodes.
 *
 *		Note that for read-only queries, after the local execution, there is no need to
 *		kick in adaptive executor.
 *
 *  There are also few limitations/trade-offs that is worth mentioning. First, the
 *  local execution on multiple shards might be slow because the execution has to
 *  happen one task at a time (e.g., no parallelism). Second, if a transaction
 *  block/CTE starts with a multi-shard command, we do not use local query execution
 *  since local execution is sequential. Basically, we do not want to lose parallelism
 *  across local tasks by switching to local execution. Third, the local execution
 *  currently only supports queries. In other words, any utility commands like TRUNCATE,
 *  fails if the command is executed after a local execution inside a transaction block.
 *  Forth, the local execution cannot be mixed with the executors other than adaptive,
 *  namely task-tracker, real-time and router executors. Finally, related with the
 *  previous item, COPY command cannot be mixed with local execution in a transaction.
 *  The implication of that any part of INSERT..SELECT via coordinator cannot happen
 *  via the local execution.
 */
2019-09-12 11:51:25 +02:00