Difference between revisions of "CREATE VIEW"
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==Syntax== | ==Syntax== | ||
| − | CREATE VIEW <filename> | (<expC>) | + | CREATE VIEW <filename> | (<expC>) [FROM ENVIRONMENT] |
| − | + | ||
| − | [FROM ENVIRONMENT] | + | |
Revision as of 10:55, 29 April 2009
Contents
Class
Terminal Developer Development Tools
Purpose
Activate the View Designer
Syntax
CREATE VIEW <filename> | (<expC>) [FROM ENVIRONMENT]
See Also
CREATE BRIDGE, CREATE SCREEN, DIALOG GET, FMT(), Function Keys, INDEX, MODIFY SCREEN, SET FORMAT, SET INDEX, SET ORDER, SET RELATION, SET VIEW, USE
Description
The CREATE VIEW command activates the full screen View Designer which is used to create a view file, which can be processed using the SET VIEW TO command. View files allow you to treat multiple databases and their associated files as a single object. Views are very useful for performing ad-hoc queries on data that is in multiple related databases.
<filename> | (<expC>)
The file name can be substituted with a <expC>, enclosed in round brackets, which returns a valid filename. If no file extension is specified, then '.vue' is used.
FROM ENVIRONMENT
If the optional FROM ENVIRONMENT clause is specified, a view file is automatically created for the established environment.
Without the FROM ENVIRONMENT clause, the CREATE VIEW command displays a screen for each workarea (1–10), prompting for the following details:
| Field | Description |
|---|---|
| Database | The name of the table to be opened in this workarea |
| Alias | The alias name for the table. By default this is the workarea letter A-J |
| Format | The screen format file to be used. (CREATE SCREEN, SET FORMAT) |
| Index (1-7) | The names of up to seven single index files (.ndx) |
| Filter | The filter expression for the table |
| Relation to | The name of a field in the current table used to link to another table |
| Into | The name of the table that is the target of the relation |
The menubar for the View Designer can be activated by pressing the [MENUBAR] key. The following options are available:
| Menu | Description |
|---|---|
| Workarea | Displays a DIALOG GET to specify the workarea number (1-10) to select |
| Databases | Displays a popup choicelist of tables in the current directory |
| Formats | Displays a popup choicelist of screen format files in the current directory |
| Indexes | Displays a popup choicelist of single index files in the current directory |
| Query | Displays a popup query builder. This is used for constructing a filter expression |
| Help | Displays the on-line help system |
A specific view file can be opened directly using the SET VIEW TO <filename> command, or by creating a VIEW BRIDGE with the CREATE BRIDGE command then issuing the USE <view bridge> command.
All Recital products support the SQL CREATE VIEW command. This creates a logical view of one or more tables based on a SELECT statement. Please see the SQL documentation for further information.
Example
create view patrons set view to patrons
Products
Recital Terminal Developer
