云服务器内容精选

  • 语法格式 创建增量物化视图 CREATE INCREMENTAL MATERIALIZED VIEW view_name AS query; 全量刷新物化视图 REFRESH MATERIALIZED VIEW view_name; 增量刷新物化视图 REFRESH INCREMENTAL MATERIALIZED VIEW view_name; 删除物化视图 DROP MATERIALIZED VIEW view_name; 查询物化视图 SELECT * FROM view_name;
  • 示例 -- 修改表的默认类型 gaussdb=# SET enable_default_ustore_table=off; -- 准备数据 CREATE TABLE t1(c1 int, c2 int); INSERT INTO t1 VALUES(1, 1); INSERT INTO t1 VALUES(2, 2); -- 创建增量物化视图 gaussdb=# CREATE INCREMENTAL MATERIALIZED VIEW mv AS SELECT * FROM t1; CREATE MATERIALIZED VIEW -- 插入数据 gaussdb=# INSERT INTO t1 VALUES(3, 3); INSERT 0 1 -- 增量刷新物化视图 gaussdb=# REFRESH INCREMENTAL MATERIALIZED VIEW mv; REFRESH MATERIALIZED VIEW -- 查询物化视图结果 gaussdb=# SELECT * FROM mv; c1 | c2 ----+---- 1 | 1 2 | 2 3 | 3 (3 rows) -- 插入数据 gaussdb=# INSERT INTO t1 VALUES(4, 4); INSERT 0 1 -- 全量刷新物化视图 gaussdb=# REFRESH MATERIALIZED VIEW mv; REFRESH MATERIALIZED VIEW -- 查询物化视图结果 gaussdb=# select * from mv; c1 | c2 ----+---- 1 | 1 2 | 2 3 | 3 4 | 4 (4 rows) -- 删除物化视图,删除表 gaussdb=# DROP MATERIALIZED VIEW mv; DROP MATERIALIZED VIEW gaussdb=# DROP TABLE t1; DROP TABLE
  • 示例 -- 修改表的默认类型 gaussdb=# set enable_default_ustore_table=off; --准备数据。 gaussdb=# CREATE TABLE t1(c1 int, c2 int); gaussdb=# INSERT INTO t1 VALUES(1, 1); gaussdb=# INSERT INTO t1 VALUES(2, 2); --创建增量物化视图。 gaussdb=# CREATE INCREMENTAL MATERIALIZED VIEW mv AS SELECT * FROM t1; CREATE MATERIALIZED VIEW --插入数据。 gaussdb=# INSERT INTO t1 VALUES(3, 3); INSERT 0 1 --增量刷新物化视图。 gaussdb=# REFRESH INCREMENTAL MATERIALIZED VIEW mv; REFRESH MATERIALIZED VIEW --查询物化视图结果。 gaussdb=# SELECT * FROM mv; c1 | c2 ----+---- 1 | 1 2 | 2 3 | 3 (3 rows) --插入数据。 gaussdb=# INSERT INTO t1 VALUES(4, 4); INSERT 0 1 --全量刷新物化视图。 gaussdb=# REFRESH MATERIALIZED VIEW mv; REFRESH MATERIALIZED VIEW --查询物化视图结果。 gaussdb=# select * from mv; c1 | c2 ----+---- 1 | 1 2 | 2 3 | 3 4 | 4 (4 rows) --删除物化视图,删除表。 gaussdb=# DROP MATERIALIZED VIEW mv; DROP MATERIALIZED VIEW gaussdb=# DROP TABLE t1; DROP TABLE
  • 语法格式 创建增量物化视图 CREATE INCREMENTAL MATERIALIZED VIEW view_name AS query; 全量刷新物化视图 REFRESH MATERIALIZED VIEW view_name; 增量刷新物化视图 REFRESH INCREMENTAL MATERIALIZED VIEW view_name; 删除物化视图 DROP MATERIALIZED VIEW view_name; 查询物化视图 SELECT * FROM view_name;
  • 语法格式 创建增量物化视图 CREATE INCREMENTAL MATERIALIZED VIEW [ view_name ] AS { query_block }; 全量刷新物化视图 REFRESH MATERIALIZED VIEW [ view_name ]; 增量刷新物化视图 REFRESH INCREMENTAL MATERIALIZED VIEW [ view_name ]; 删除物化视图 DROP MATERIALIZED VIEW [ view_name ]; 查询物化视图 SELECT * FROM [ view_name ];
  • 示例 --准备数据。openGauss=# CREATE TABLE t1(c1 int, c2 int);openGauss=# INSERT INTO t1 VALUES(1, 1);openGauss=# INSERT INTO t1 VALUES(2, 2);--创建增量物化视图。openGauss=# CREATE INCREMENTAL MATERIALIZED VIEW mv AS SELECT * FROM t1;CREATE MATERIALIZED VIEW--插入数据。openGauss=# INSERT INTO t1 VALUES(3, 3);INSERT 0 1--增量刷新物化视图。openGauss=# REFRESH INCREMENTAL MATERIALIZED VIEW mv;REFRESH MATERIALIZED VIEW--查询物化视图结果。openGauss=# SELECT * FROM mv; c1 | c2 ----+---- 1 | 1 2 | 2 3 | 3(3 rows)--插入数据。openGauss=# INSERT INTO t1 VALUES(4, 4);INSERT 0 1--全量刷新物化视图。openGauss=# REFRESH MATERIALIZED VIEW mv;REFRESH MATERIALIZED VIEW--查询物化视图结果。openGauss=# select * from mv; c1 | c2 ----+---- 1 | 1 2 | 2 3 | 3 4 | 4(4 rows)--删除物化视图。openGauss=# DROP MATERIALIZED VIEW mv;DROP MATERIALIZED VIEW