Choose your database:
AnySQL
MySQL
MS SQL Server
PostgreSQL
SQLite
Firebird
Oracle
SQL Anywhere
DB2
MaxDB

Subscribe to our news:
Partners
Testimonials
Jonathan Oakes: "This is a lovely application. It's easy to hook into my own bespoke applications. It's very powerful, yet really quite simple to use. Thanks for this".
David Lantz: "Thank you, this is by far the simplest, and most friendly utility for building db record system I have ever used. I wish I could get my systems guys at the office to purchase this for our company would be so very helpful and speed up a lot of work. I for one have used it for everything from a simple inventory record of my house, to a members record for my church just little pet projects and a test bed to test my own db builds and theories before having to hand code at the office..... it is a lot of fun to work with".

More

Add your opinion

Customers
Download Buy

PHP Generator for MySQL online Help

Prev Return to chapter overview Next

Calculated Columns

Calculated (AKA computed, generated, or virtual) columns are columns that do not exist in the data source the page is based on and their values are automatically computed using other column values or another deterministic expression.  For example, you might create a string column that displays concatenated values from other fields, create an integer column to calculate the person age based on his birthday, and so on.

 

Creating calculated columns

To create a new calculated column, open Page Editor, right-click the grid at the Columns tab and choose Add calculated column... from the popup menu. The following window will be opened:

 

 

Provide the name, the data type and the caption for the new column and press OK. A new calculated column will be added to the column list. To quickly distinguish between ordinal and calculated fields, the latter are marked with a green calculator icon.

 

It is possible to add multiple calculated columns for a single page.

 

Dropping calculated columns

To drop an existing calculated column, select the column in the column list, right-click and choose Drop calculated column from the popup menu.

 

Compute column values

To compute column values in read-only views (List, Print, Export, etc) provide the OnCalculateFields server-side event handler. For Edit and Insert forms provide the OnCalculateControlValues client-side event handler.

 

Use totals

Check this option to aggregate values this calculated column, specify the Aggregate expression (like SUM(quantity*price) where quantity and price are the table column names) and the Aggregate caption. Total content of calculated columns can be customized via OnCustomRenderTotals event.

 

Restrictions

Calculated columns cannot be used with Data Filtering and Multi-Edit tools, so the corresponding options in the column list are always disabled.



Prev Return to chapter overview Next