When initializing a Citus formation automatically from an external piece of
software such as Citus-HA, the following process process may be used:
- decide on the groupId in the external software
- SELECT * FROM master_add_inactive_node('localhost', 9701, groupid => X)
When Citus checks for maxGroupId, it forbids other software to pick their
own group Ids to ues with the master_add_inactive_node() API.
This patch removes the extra testing around maxGroupId.
Description: Support round-robin `task_assignment_policy` for queries to reference tables.
This PR allows users to query multiple placements of shards in a round robin fashion. When `citus.task_assignment_policy` is set to `'round-robin'` the planner will use a round robin scheduling feature when multiple shard placements are available.
The primary use-case is spreading the load of reference table queries to all the nodes in the cluster instead of hammering only the first placement of the reference table. Since reference tables share the same path for selecting the shards with single shard queries that have multiple placements (`citus.shard_replication_factor > 1`) this setting also allows users to spread the query load on these shards.
For modifying queries we do not apply a round-robin strategy. This would be negated by an extra reordering step in the executor for such queries where a `first-replica` strategy is enforced.
The file handling the utility functions (DDL) for citus organically grew over time and became unreasonably large. This refactor takes that file and refactored the functionality into separate files per command. Initially modeled after the directory and file layout that can be found in postgres.
Although the size of the change is quite big there are barely any code changes. Only one two functions have been added for readability purposes:
- PostProcessIndexStmt which is extracted from PostProcessUtility
- PostProcessAlterTableStmt which is extracted from multi_ProcessUtility
A README.md has been added to `src/backend/distributed/commands` describing the contents of the module and every file in the module.
We need more documentation around the overloading of the COPY command, for now the boilerplate has been added for people with better knowledge to fill out.
Nils Dijk
Nils Dijk
Murat Tuncer
Murat Tuncer
Marco Slot
Jason Petersen
Dimitri Fontaine
Marco Slot
hanefi
Önder Kalacı
Burak Velioglu
velioglu