Help Center> GaussDB(DWS)> 8.2.0> Hybrid Data Warehouse> Support and Constraints
Updated on 2023-04-19 GMT+08:00

Support and Constraints

A hybrid data warehouse is compatible with all column-store syntax.

Table 1 Supported syntax

Syntax

Supported

CREATE TABLE

Yes

CREATE TABLE LIKE

Yes

DROP TABLE

Yes

INSERT

Yes

COPY

Yes

SELECT

Yes

TRUNCATE

Yes

EXPLAIN

Yes

ANALYZE

Yes

VACUUM

Yes

ALTER TABLE DROP PARTITION

Yes

ALTER TABLE ADD PARTITION

Yes

ALTER TABLE SET WITH OPTION

Yes

ALTER TABLE DROP COLUMN

Yes

ALTER TABLE ADD COLUMN

Yes

ALTER TABLE ADD NODELIST

Yes

ALTER TABLE CHANGE OWNER

Yes

ALTER TABLE RENAME COLUMN

Yes

ALTER TABLE TRUNCATE PARTITION

Yes

CREATE INDEX

Yes

DROP INDEX

Yes

DELETE

Yes

Other ALTER TABLE syntax

Yes

ALTER INDEX

Yes

MERGE

Yes

SELECT INTO

Yes

UPDATE

Yes

CREATE TABLE AS

Yes

Constraints

  1. To use HStore tables, use the following parameter settings, or the performance of HStore tables will deteriorate significantly:

    autovacuum_max_workers_hstore=3, autovacuum_max_workers=6, and autovacuum=true

  2. Currently, HStore and column storage do not support the use of VACUUM to clear dirty index data, and frequent updates may cause index bloat. This function will be supported in later versions.