CREATE VIEW

description

该语句用于创建一个逻辑视图

语法：

CREATE VIEW [IF NOT EXISTS]
[db_name.]view_name
(column1[ COMMENT "col comment"][, column2, ...])
AS query_stmt

说明：

1. 视图为逻辑视图，没有物理存储。所有在视图上的查询相当于在视图对应的子查询上进行。

2. query_stmt 为任意支持的 SQL

Example

1. 在 example_db 上创建视图 example_view

   CREATE VIEW example_db.example_view (k1, k2, k3, v1)
   AS
   SELECT c1 as k1, k2, k3, SUM(v1) FROM example_table
   WHERE k1 = 20160112 GROUP BY k1,k2,k3;

2. 创建一个包含 comment 的 view

   CREATE VIEW example_db.example_view
   (
   k1 COMMENT "first key",
   k2 COMMENT "second key",
   k3 COMMENT "third key",
   v1 COMMENT "first value"
   )
   COMMENT "my first view"
   AS
   SELECT c1 as k1, k2, k3, SUM(v1) FROM example_table
   WHERE k1 = 20160112 GROUP BY k1,k2,k3;

keyword

CREATE,VIEW