ExecuteTaskListExtended is the common method for different codepaths,
and instead of writing separate local execution logics in different
codepaths, it makes more sense to have the logic here. We still need to
do some refactoring, this is an initial step.
After this commit, we can run create shard commands locally. There is a
special case with shard creation commands. A create shard command might
have a concatenated query string, however local execution did not know
how to execute a task with multiple query strings. This is also
implemented in this commit. We go over each query in the concatenated
query string and plan/execute them one by one.
A more clean solution to this would be to make sure that each task has a
single query. We currently cannot do that because we need to ensure the
task dependencies. However, it would make sense to do that at some point
and it would simplify the code a lot.
It seems that one of the deadlock detection tests fails way too often in
our CI. The difference is only ordering. Currently it seems that it is a
good idea to disable this test for the sake of development.
ExecuteLocalTaskList doesn't need scanState as it only uses
paramListInfo, distributedPlan and tupleStoreState. It is better to pass
only the variables that the function needs, so that we can call this
function from other places when we dont have scanState.
We sometimes get no output timeout in our cirleci jobs. There is no
point in waiting for 10 minutes to get those timeouts. Ideally we should
see some output, this will also prevent adding a test that takes longer
than 2 mins to run.
We had many fields in task related to query strings. It was kind of
complex, and only of them could be set at a time. Therefore it makes
more sense to abstract this and use a union so that it is clear that
only of them should be set.
We have three fields that could have query related strings:
- queryForLocation
- queryStringLazy
- perPlacementQueryStrings
Relatively, they can be set with:
- SetTaskQueryString
- SetTaskQueryIfShouldLazyDeparse
- SetTaskPerPlacementQueryStrings
The direct usage of the query related fields are also removed.
Rename queryForLocalExecution
Currently queryForLocalExecution is only used for deparsing purposes,
therefore it makes sense to rename it to what it is doing.
TaskQueryStringForPlacement simplifies how the executor gets the query
string for a given placement. Task will use the necessary fields to
return the correct query placement string. Executor doesn't need to know
the details for this.
rename TaskQueryString as TaskQueryStringAllPlacements
TaskQueryString returns the query string that will be the same for all
the placements. In INSERT..SELECT the query string can be different for
each placement. Adaptive executor uses TaskQueryStringForPlacement,
which returns the query string for a placement. It makes sense to rename
TaskQueryString as TaskQueryStringAllPlacements as it is returning the
query string for all placements.
rename SetTaskQuery as SetTaskQueryIfShouldLazyDeparse
SetTaskQuery does not always sets the task query. It can set the query
string as well. So it is more clear to name it
SetTaskQueryIfShouldLazyDeparse, since it will set the query not query
string only when we should deparse the query in a lazy way.
It is possible that a task will have different query string for each
placement. This is the case in INSERT..SELECT via repartitioning. When
we are setting task->perPlacementQueryString, we should set
queryStringLazy to NULL. Therefore a method for that purpose is created.
In PostgreSQL, user defaults for config parameters can be changed by
ALTER ROLE .. SET statements. We wish to propagate those defaults
across the Citus cluster so that the behavior will be similar in
different workers.
The defaults can either be set in a specific database, or the whole
cluster, similarly they can be set for a single role or all roles.
We propagate the ALTER ROLE .. SET if all the conditions below are met:
- The query affects the current database, or all databases
- The user is already created in worker nodes
In PostgreSQL, user defaults for config parameters can be changed by
ALTER ROLE .. SET statements. We wish to propagate those defaults
accross the Citus cluster so that the behaviour will be similar in
different workers.
The defaults can either be set in a specific database, or the whole
cluster, similarly they can be set for a single role or all roles.
We propagate the ALTER ROLE .. SET if all the conditions below are met:
- The query affects the current database, or all databases
- The user is already created in worker nodes
Sometimes we have concatenated query strings for a task. However,
when we want to find each query string, it is not a trivial task.
Therefore, it makes sense to store this in task so that when we need
each query string we can easily get it.
Some refactoring:
Consolidate expression which decides whether GROUP BY/HAVING are pushed down
Rename early pullUpIntermediateRows to hasNonDistributableAggregates
Create WorkerColumnName to handle formatting WORKER_COLUMN_FORMAT
Ignore NULL StringInfo pointers to SafeToPushdownWindowFunction
Fix bug where SubqueryPushdownMultiNodeTree mutates supplied Query,
SafeToPushdownWindowFunction requires the original query as it relies on rtable
DESCRIPTION: Refactor dependency resolution and resolve from pg_shdepend
This PR refactors how dependencies are resolved by not assuming solely a `pg_depend` record describing the dependency. Instead we keep a definition of the dependency around which records how the dependency is resolved. This can be one of the following ways
- `pg_depend`, data will contain a copy of the `pg_depend` record
- `pg_shdepend`, data will contain a copy of the `pg_shdepend` record
- `ObjectAddress`, data will contain only an `ObjectAddress` describing a dependency
Irregardless of way the dependency was found it will always be able to get to the address of the dependency as that is the most important property.
For some checks we can inspect the source where the dependency was found and perform a deep inspection to decide if we want to follow the dependency. This is important to not distribute dependencies coming from extensions for example.
Marco Slot
SaitTalhaNisanci
Philip Dubé
Philip Dubé
Hadi Moshayedi
Marco Slot
Onur Tirtir
Jelte Fennema
Hanefi Onaldi
Hanefi Onaldi
Nils Dijk