Specifications

20 – Using PlantScape Data in Other Applications
400 R400
A table opened in this way displays every point field for every point of that type
in the PlantScape server database. This might be more information than is
needed.
To select particular data out of the table, you need to build a query. A query can
be used to reduce the number of columns (point fields) or rows (points) which
are retrieved from the database. In some client applications a wizard will assist
you to build a query; the application converts this query to SQL before sending it
to the ODBC driver. A query built using a Microsoft Access wizard is shown
below. It selects all point fields for all status points currently in alarm.
The SQL equivalent of the above query is:
SELECT StatusPoint.*
FROM StatusPoint
WHERE StatusPoint.InAlarm=1;
Flexible Point tables might be too large to open and view without filtering. To
retrieve information from very large tables you need to set up a query that
specifies the required parameters.For information about setting up queries on
control module points, see “SQL Query on ControlModulePoint Table” on
page 401.
The first 28 columns in the Flexible Point table (see Figure 20.2, “Point Data That
You Can Access” on page 399) are common to all flexible points and can be
accessed by name. The other columns are parameters of the particular kind of
flexible point.
Figure 20.3 Microsoft Access Query
plscpcg.book Page 400 Monday, May 28, 2001 10:11 AM