DISPLAY DATABASE

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Purpose

Display information about the active database


Syntax

DISPLAY DATABASE [TO FILE <.txt filename> | (<expC>)] | [TO PRINT]


See Also

ADATABASES(), ALTER INDEX, ALTER TABLE, CLOSE DATABASES, CLOSE TABLES, COMPILE DATABASE, COPY DATABASE, CREATE DATABASE, CREATE INDEX, CREATE TABLE, CREATE VIEW, DB_DATADIR, DB_PRINT, DBUSED(), DISPLAY INDEXES, DISPLAY SCHEMAS, DISPLAY TABLES, DROP DATABASE, DROP INDEX, DROP TABLE, Function Keys, GETENV(), LIST DATABASE, LIST INDEXES, LIST SCHEMAS, LIST TABLES, OPEN DATABASE, SET EXCLUSIVE, SET PAGELENGTH, SET PAGEWIDTH, SET PRINTER, USE


Description

The DISPLAY DATABASE command is used to display information about the currently active database. Databases in Recital are implemented as directories containing files that correspond to the tables and associated files in the database. Operating System file protection can be applied individually to the files for added security. The directories are sub-directories of the Recital data directory. The environment variable / symbol DB_DATADIR points to the current Recital data directory and can be queried using the GETENV() function. Files from other directories can be added to the database using the ADD TABLE command or via the database catalog and SET AUTOCATALOG functionality. Databases are opened using the OPEN DATABASE command.

The DISPLAY DATABASE command displays the following information:

  • Database Name, e.g. southwind
  • Database Path, e.g. /usr/recital/data/southwind

and for each table in the database the equivalent of DISPLAY STRUCTURE INDEX followed by DISPLAY DICTIONARY:

  • Table file name
  • Number of records
  • Date of creation
  • Date of last update
  • Encryption status
  • Field names, types, sizes and description
  • Total record length
  • Production DBX file name
  • Index tag names, keys, types and lengths
  • Dictionary information


DISPLAY commands differ from LIST commands in that they pause every 17 lines until a key is pressed. You can cancel any further output at this point by pressing the [ABANDON] key. Where the output is sent to a file or printer, the pause is disabled.


Keyword Description
TO <file> The display output will be sent to the specified file. The filename can be substituted with a <expC>, enclosed in round brackets, which returns a valid filename. If no file extension is specified, then ".txt" will be used. The command SET PAGELENGTH governs the output file pagination and SET PAGEWIDTH defines the width of each page. Page numbers are centered on the bottom of the page according to width.
TO PRINT The display output will be sent to a printer. The TO PRINT option will default to a local printer unless the command SET PRINTER TO \\SPOOLER is issued. The print request will then be spooled to the system printer, which is defined by the environment variable DB_PRINT.


Example

set sql to vfp
open database southwind
display database to file sw_info


Products

Recital Server, Recital