We used to only support pushdownable set operations inside a
subquery, however, we could easily expand the restriction
checks to cover top level set operations as well.
We use PostgreSQL hooks to accumulate the join restrictions
and PostgreSQL gives us all the join paths it tries while
deciding on the join order. Thus, for queries that have many
joins, this function is likely to remove lots of duplicate join
restrictions. This becomes relevant for Citus on query pushdown
check peformance.
We were allowing count distict queries even if they were
not directly on columns if the query is grouped on
distribution column.
When performing these checks we were skipping subqueries
because they also perform this check in a more concise manner.
We relied on oid SUBQUERY_RELATION_ID (10000) to decide if
a given RTE relation id denotes a subquery, however, we also
use SUBQUERY_PUSHDOWN_RELATION_ID (10001) for some subqueries.
We skip both type of subqueries with this change.
VLAs aren't supported by Visual Studio.
- Remove all existing instances of VLAs.
- Add a flag, -Werror=vla, which makes gcc refuse to compile if we add
VLAs in the future.
- variable length arrays (VLAs) do not work with Visual Studio
- fix an off-by-one error. We incorrectly assumed there would always at
least as many edges as there were nodes.
- refactor: reduce scope of transactionNodeStack by moving it into the
function which uses it.
- refactor: break up the distinct uses of currentStackDepth into
separate variables.
It's against our coding convention to call functions inside parameter
lists; when single-stepping with a debugger it's difficult to determine
what the function returned.
That wouldn't be good enough reason to change this code but while
porting Citus to Windows I ran into this line of code.
assign_distributed_transaction_id was called with a weird timestamp and
I wasn't able to find the problem without first making this change.
* Don't use expressions inside compound statements
* Don't depend on __builtin_constant_p
* Remove reliance on S_ISLNK
* Replace use of __func__: older mcvs doesn't support this builtin
With this fix, we traverse the graph with DFS which was originally
intended. Note that, before the fix, we traverse the graph with BFS
which might lead to killing some unrelated backend that is not
involved in the distributed deadlock.
By sharing the implementation of the function AppendOptionListToString on
three call sites, we would expand an extra OPTIONS keyword in a create index
statement, and omit other bits of the specific syntax here.
This patch introduces an AppendStorageParametersToString() function that is
very similar to AppendOptionListToString() but handles WITH(a="foo",...)
syntax that is used in reloptions (aka Storage Parameters).
Fixes#1747.
PostgreSQL implements support for several relation kinds in a single
statement, such as in the AlterTableStmt case, which supports both tables
and indexes and more (see ATExecSetRelOptions in PostgreSQL source code file
src/backend/commands/tablecmds.c for an example of that).
As a consequence, this patch implements support for setting and resetting
storage parameters on both relation kinds.
The command is now distributed among the shards when the table is
distributed. To that effect, we fill in the DDLJob's targetRelationId with
the OID of the table for which the index is defined, rather than the OID of
the index itself.
Citus sometimes have regressions around non-default schema support, meaning
not public and not in the search_path, per @marcocitus. This patch changes
some regression tests to use a non-default schema in order to cover more
cases.
The implementation was already mostly in place, but the code was protected
by a principled check against the operation. Turns out there's a nasty
concurrency bug though with long identifier names, much as in #1664.
To prevent deadlocks from happening, we could either review the DDL
transaction management in shards and placements, or we can simply reject
names with (NAMEDATALEN - 1) chars or more — that's because of the
PostgreSQL array types being created with a one-char prefix: '_'.
We shouldn't return in middle of a PG_TRY() block because if we do, we won't reset PG_exception_stack, and later when a re-throw tries to jump to the jump-point which was active in this PG_TRY() block, it seg-faults.
We used to return in middle of PG_TRY() block in WaitForConnections() where we checked for cancellations. Whenever cancellations were caught here, Citus crashed. And example was reported by @onderkalaci at #1903.
clause is not supported
This change allows unsupported clauses to go through query pushdown
planner instead of erroring out as we already do for non-outer joins.
Onder Kalaci
Marco Slot
Markus Sintonen
velioglu
Murat Tuncer
metdos
Brian Cloutier
Brian Cloutier
Hadi Moshayedi
Dimitri Fontaine
Marco Slot
mehmet furkan şahin