mirror of https://github.com/citusdata/citus.git
fa7b8949a8
Support pushdown query where all the tables in the merge-sql are Citus-distributed, co-located, and both
the source and target relations are joined on the distribution column. This will generate multiple tasks
which execute independently after pushdown.
SELECT create_distributed_table('t1', 'id');
SELECT create_distributed_table('s1', 'id', colocate_with => ‘t1’);
MERGE INTO t1
USING s1
ON t1.id = s1.id
WHEN MATCHED THEN
UPDATE SET val = s1.val + 10
WHEN MATCHED THEN
DELETE
WHEN NOT MATCHED THEN
INSERT (id, val, src) VALUES (s1.id, s1.val, s1.src)
*The only exception for both the phases II and III is, UPDATEs and INSERTs must be done on the same shard-group
as the joined key; for example, below scenarios are NOT supported as the key-value to be inserted/updated is not
guaranteed to be on the same node as the id distribution-column.
MERGE INTO target t
USING source s ON (t.customer_id = s.customer_id)
WHEN NOT MATCHED THEN - -
INSERT(customer_id, …) VALUES (<non-local-constant-key-value>, ……);
OR this scenario where we update the distribution column itself
MERGE INTO target t
USING source s On (t.customer_id = s.customer_id)
WHEN MATCHED THEN
UPDATE SET customer_id = 100;
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| .. | ||
| clock | ||
| commands | ||
| connection | ||
| deparser | ||
| executor | ||
| metadata | ||
| operations | ||
| planner | ||
| progress | ||
| relay | ||
| replication | ||
| shardsplit | ||
| sql | ||
| test | ||
| transaction | ||
| utils | ||
| worker | ||
| .gitignore | ||
| Makefile | ||
| citus--11.1-1.control | ||
| citus.control | ||
| safeclib | ||
| shared_library_init.c | ||