Index for Section VIEW

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CREATE
NAME
  CREATE VIEW - define a new view

SYNOPSIS
  CREATE [ OR REPLACE ] VIEW view [ ( column name list ) ] AS SELECT query

  INPUTS

  view The name (optionally schema-qualified) of a view to be created.

  column name list
       An optional list of names to be used for columns of the view.  If
       given, these names override the column names that would be deduced
       from the SQL query.

  query
       An SQL query (that is, a SELECT statement) which will provide the
       columns and rows of the view.

       Refer to SELECT [select(5)] for more information about valid
       arguments.

  OUTPUTS

  CREATE VIEW
       The message returned if the view is successfully created.

  ERROR: Relation 'view' already exists
       This error occurs if the view specified already exists in the
       database.

  WARNING: Attribute 'column' has an unknown type
       The view will be created having a column with an unknown type if you
       do not specify it. For example, the following command gives a warning:

       CREATE VIEW vista AS SELECT 'Hello World'

       whereas this command does not:

       CREATE VIEW vista AS SELECT text 'Hello World'

DESCRIPTION
  CREATE VIEW defines a view of a query.  The view is not physically
  materialized. Instead, a query rewrite rule (an ON SELECT rule) is
  automatically generated to support SELECT operations on views.

  CREATE OR REPLACE VIEW is similar, but if a view of the same name already
  exists, it is replaced. You can only replace a view with a new query that
  generates the identical set of columns (i.e., same column names and data
  types).

  If a schema name is given (for example, CREATE VIEW myschema.myview ...)
  then the view is created in the specified schema. Otherwise it is created
  in the current schema (the one at the front of the search path; see
  CURRENT_SCHEMA()).  The view name must be distinct from the name of any
  other view, table, sequence, or index in the same schema.

  NOTES

  Currently, views are read only: the system will not allow an insert,
  update, or delete on a view. You can get the effect of an updatable view by
  creating rules that rewrite inserts, etc. on the view into appropriate
  actions on other tables. For more information see CREATE RULE
  [create_rule(5)].

  Use the DROP VIEW statement to drop views.

USAGE
  Create a view consisting of all Comedy films:

  CREATE VIEW kinds AS
      SELECT *
      FROM films
      WHERE kind = 'Comedy';

  SELECT * FROM kinds;

   code	 |	     title	     | did | date_prod	|  kind	 | len
  -------+---------------------------+-----+------------+--------+-------
   UA502 | Bananas		     | 105 | 1971-07-13 | Comedy | 01:22
   C_701 | There's a Girl in my Soup | 107 | 1970-06-11 | Comedy | 01:36
  (2 rows)

COMPATIBILITY
  SQL92

  SQL92 specifies some additional capabilities for the CREATE VIEW statement:

  CREATE VIEW view [ column [, ...] ]
      AS SELECT expression [ AS colname ] [, ...]
      FROM table [ WHERE condition ]
      [ WITH [ CASCADE | LOCAL ] CHECK OPTION ]

  The optional clauses for the full SQL92 command are:

  CHECK OPTION
       This option is to do with updatable views.  All INSERT and UPDATE
       commands on the view will be checked to ensure data satisfy the view-
       defining condition. If they do not, the update will be rejected.

  LOCAL
       Check for integrity on this view.

  CASCADE
       Check for integrity on this view and on any dependent view. CASCADE is
       assumed if neither CASCADE nor LOCAL is specified.

  CREATE OR REPLACE VIEW is a PostgreSQL language extension.

Index for Section VIEW

Alphabetical listing for C

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