Fixing a division by zero in the cost calculations for scanning a columnar table.
Due to how the columns in a columnar table are counted an empty table would result in a division by zero. Instead this patch keeps the column selection ratio on zero when this happens, resulting in an accurate cost of zero pages to scan a columnar table.
fixes#4589
* Make undistribute_table() and citus_create_local_table() work with columnar
* Rename and use LocallyExecuteUtilityTask for UDF check
* Remove 'local' references in ExecuteUtilityCommand
/*
* Creating Citus local tables relies on functions that accesses
* shards locally (e.g., ExecuteAndLogDDLCommand()). As long as
* we don't teach those functions to access shards remotely, we
* cannot relax this check.
*/
Logical replication status can take wal_receiver_status_interval
seconds to get updated. Default is 10s, which means tests in
which logical replication is used can take a long time to finish.
We reduce it to 1 second to speed these tests up.
Logical replication apply launcher launches workers every
wal_retrieve_retry_interval, so if we have many shard moves with
logical replication consecutively, they will be throttled by this
parameter. Default is 5s, we reduce it to 1s so we finish tests
faster.
The reason behind skipping postgres tables is that we support
foreign keys between postgres tables and reference tables
(without converting postgres tables to citus local tables)
when enable_local_reference_table_foreign_keys is false or
when coordinator is not added to metadata.
When enabled any foreign keys between local tables and reference
tables supported by converting the local table to a citus local
table.
When the coordinator is not in the metadata, the logic is disabled
as foreign keys are not allowed in this configuration.
If relation is not involved in any foreign key relationships,
foreign key graph would not return any relations for given
relationId as expected.
But even if it's the case, we should still undistribute the table
itself.
DESCRIPTION: Add tests to verify crash recovery for columnar tables
Based on the Postgres TAP tooling we add a new test suite to the array of test suites for citus. It is modelled after `src/test/recovery` in the postgres project and takes the same place in our repository. It uses the perl modules defined in the postgres project to control the postgres nodes.
The test we add here focus on crash recovery. Our follower tests should cover the streaming replication behaviour.
It is hooked to our CI for both postgres 12 and postgres 13. We omit the recovery tests for postgres 11 as we do not have support for the columnar table access method.
* Stronger check for triggers on columnar tables (#4493).
Previously, we used a simple ProcessUtility_hook. Change to use an
object_access_hook instead.
* Replace alter_table_set_access_method test on partition with foreign key
Co-authored-by: Jeff Davis <jefdavi@microsoft.com>
Co-authored-by: Marco Slot <marco.slot@gmail.com>
With citus shard helper view, we can easily see:
- where each shard is, which node, which port
- what kind of table it belongs to
- its size
With such a view, we can see shards that have a size bigger than some
value, which could be useful. Also debugging can be easier in production
as well with this view.
Fetch shards in one go per node
The previous implementation was slow because it would do a lot of round
trips, one per shard to be exact. Hence it is improved so that we fetch
all the shard_name, shard-size pairs per node in one go.
Construct shards_names, sizes query on coordinator
* Replace master_add_node with citus_add_node
* Replace master_activate_node with citus_activate_node
* Replace master_add_inactive_node with citus_add_inactive_node
* Use master udfs in old scripts
* Replace master_add_secondary_node with citus_add_secondary_node
* Replace master_disable_node with citus_disable_node
* Replace master_drain_node with citus_drain_node
* Replace master_remove_node with citus_remove_node
* Replace master_set_node_property with citus_set_node_property
* Replace master_unmark_object_distributed with citus_unmark_object_distributed
* Replace master_update_node with citus_update_node
* Replace master_update_shard_statistics with citus_update_shard_statistics
* Replace master_update_table_statistics with citus_update_table_statistics
* Rename master_conninfo_cache_invalidate to citus_conninfo_cache_invalidate
Rename master_dist_local_group_cache_invalidate to citus_dist_local_group_cache_invalidate
* Replace master_copy_shard_placement with citus_copy_shard_placement
* Replace master_move_shard_placement with citus_move_shard_placement
* Rename master_dist_node_cache_invalidate to citus_dist_node_cache_invalidate
* Rename master_dist_object_cache_invalidate to citus_dist_object_cache_invalidate
* Rename master_dist_partition_cache_invalidate to citus_dist_partition_cache_invalidate
* Rename master_dist_placement_cache_invalidate to citus_dist_placement_cache_invalidate
* Rename master_dist_shard_cache_invalidate to citus_dist_shard_cache_invalidate
* Drop master_modify_multiple_shards
* Rename master_drop_all_shards to citus_drop_all_shards
* Drop master_create_distributed_table
* Drop master_create_worker_shards
* Revert old function definitions
* Add missing revoke statement for citus_disable_node
CREATE TABLE does not invalidate foreign key graph but some other set of
ddl commands do.
Previously, as we run multi_foreign_key & multi_foreign_key_relation_graph
in parallel, it's possible that multi_foreign_key invalidates foreign key
graph via some ddl commands and create table test in
multi_foreign_key_relation_graph becomes flaky.
So we un-parallelize those two tests.
* Rethrow original concurrent index creation failure message
* Alter test outputs for concurrent index creation
* Detect duplicate table failure in concurrent index creation
* Add test for conc. index creation w/out duplicates
* Prevent deadlock for long named partitioned index creation on single node
* Create IsSingleNodeCluster function
* Use both local and sequential execution
On top of our foreign key graph, implement the infrastructure to get
list of relations that are connected to input relation via a foreign key
graph.
We need this to support cascading create_citus_local_table &
undistribute_table operations.
Also add regression tests to see what our foreign key graph is able to
capture currently.
Attribute number in a subquery RTE and relation RTE means different
things. In a relation attribute number will point to the column number
in the table definition including the dropped columns as well however in
subquery, it means the index in the target list. When we convert a
relation RTE to subquery RTE we should either correct all the relevant
attribute numbers or we can just add a dummy column for the dropped
columns. We choose the latter in this commit because it is practically
too vulnerable to update all the vars in a query.
Another thing this commit fixes is that in case a join restriction
clause list contains a false clause, we should just returns a false
clause instead of the whole list, because the whole list will contain
restrictions from other RTEs as well and this breaks the query, which
can be seen from the output changes, now it is much simpler.
Also instead of adding single tests for dropped columns, we choose to
run the whole mixed queries with tables with dropped columns, this
revealed some bugs already, which are fixed in this commit.