GBase 8a MPP Cluster 产品手册 5 数据库管理指南 文档版本953(2022-09-15) 南大通用数据技术股份有限公司 988 语法格式 ALTER VIEW [vc_name.][database_name.]view_name [(column_list)] AS select_statement 表5- 70 参数说明 参数名称 说 明 vc_name vc 名,可选项。 database_name 数据库名,可选项。 view_name 视图名。 column_list 修改的视图列列表。 select_statement 提供给定义视图的SELECT 语句。本语句可以从其它表或者 视图中提取数据。 示例 示例1:修改视图v_t 中的列为指定列。 gbase> CREATE TABLE t (name VARCHAR(20),address VARCHAR(40),sex INT); Query OK, 0 rows affected (Elapsed: 00:00:00.06) gbase> CREATE VIEW v_t AS SELECT * FROM t; Query OK, 0 rows affected (Elapsed: 00:00:00.05) gbase> INSERT INTO t VALUES('TOM','east street','23'),('jack','west road NO 15','22'),('MIKE','DongFang road NO 22','21'),('TONY','EA Street','34'),('Rose','TangRen Street NO.191','31'); Query OK, 5 rows affected (Elapsed: 00:00:00.05) Records: 5 Duplicates: 0 Warnings: 0 gbase> DESC v_t; +---------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +---------+-------------+------+-----+---------+-------+ | name | varchar(20) | YES | | NULL | | | address | varchar(40) | YES | | NULL | | | sex | int(11) | YES | | NULL | | +---------+-------------+------+-----+---------+-------+ 3 rows in set (Elapsed: 00:00:00.01)
GBase 8a MPP Cluster 产品手册 5 数据库管理指南 文档版本953(2022-09-15) 南大通用数据技术股份有限公司 989 gbase> SELECT * FROM v_t; +------+-----------------------+------+ | name | address | sex | +------+-----------------------+------+ | TOM | east street | 23 | | jack | west road NO 15 | 22 | | MIKE | DongFang road NO 22 | 21 | | TONY | EA Street | 34 | | Rose | TangRen Street NO.191 | 31 | +------+-----------------------+------+ 5 rows in set (Elapsed: 00:00:00.03) gbase> ALTER VIEW v_t(a,b) AS SELECT name,address FROM t; Query OK, 0 rows affected (Elapsed: 00:00:00.07) gbase> DESC v_t; +-------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+-------+ | a | varchar(20) | YES | | NULL | | | b | varchar(40) | YES | | NULL | | +-------+-------------+------+-----+---------+-------+ 2 rows in set (Elapsed: 00:00:00.00) gbase> SELECT * FROM v_t; +------+-----------------------+ | a | b | +------+-----------------------+ | TOM | east street | | jack | west road NO 15 | | MIKE | DongFang road NO 22 | | TONY | EA Street | | Rose | TangRen Street NO.191 | +------+-----------------------+ 5 rows in set (Elapsed: 00:00:00.02)