CREATE VIEW

Description

This statement is used to create a logical view
Grammar:
    CREATE VIEW [IF NOT EXISTS]
    [db_name.]view_name
    (column1[ COMMENT "col comment"][, column2, ...])
    AS query_stmt
Explain:
    1. Views are logical views without physical storage. All queries on views are equivalent to sub-queries corresponding to views.
    2. query_stmt is arbitrarily supported SQL.

example

1. Create view example_view on example_db
    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. Create view with comment
    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