ALTER VIEW

description

This statement is used to modify the definition of a view。

Syntax:

ALTER VIEW
[db_name.]view_name
(column1[ COMMENT "col comment"][, column2, ...])
AS query_stmt

Note:

  1. View is logical, where the data isn't stored in the physical medium. The view will be used as a subquery in the statement when queried. Therefore, modifying the definition of views is equivalent to modifying query_stmt.
  2. query_stmt is arbitrarily supported SQL.

example

  1. Alter example_view on example_db.

    ALTER VIEW example_db.example_view
    (
    c1 COMMENT "column 1",
    c2 COMMENT "column 2",
    c3 COMMENT "column 3"
    )
    AS SELECT k1, k2, SUM(v1) 
    FROM example_table
    GROUP BY k1, k2