Calculated Report Columns

Introduction

In addition to report columns derived from tables, you can also create columns which display data derived from other report columns. These data are not stored in or retrieved from any database table. The value of a calculated column is determined on the basis of other columns in the report, including other calculated columns. To refer to other calculated columns in an expression, use their column numbers.

Example: The Days Late column (#26) in theAGEDEBTCUST2report indicates the number of days that have passed since payment was due by comparing today's date (SQL.DATE8 — an SQL variable) to the payment date (column #5):
0+ (SQL.DATE8 - (#5) > 0 ? (SQL.DATE8 - (#5))/24:00 : 0)

Note the use of a question mark and colon to form an if-then-else expression. Roughly, this means: if the difference between today's date and the payment date is greater than 0, then divide that difference by 24 hours (to convert it into days); otherwise, display 0.

Steps for Creating a Calculated Column

To add a calculated column to a given report, take the following steps:

  1. In the Report Columnsform, specify the position of the calculated column in the Poscolumn.
  2. Designate the column’s width in the Width column. In the case of a real number or a shifted integer, designate decimal precision as well.
  3. Specify the column title in the Revised Title column. Note that, unlike regular report columns, which inherit titles from their respective table columns, calculated columns have to be assigned titles. If you forget to do so, the column will remain untitled when the report is run.
  4. Enter the sub-level form, Report Column Extension.
  5. Write the expression that determines the value of the column in the Expression/Condition column, using SQL syntax. If there is not enough room for the entire expression, continue it in the sub-level form, Expression/Condition (cont.).
  6. Designate the column type (e.g., CHAR, INT, REAL) in the Column Type column of the Report Column Extensionform.

Notes:

  • You can quickly view all calculated columns in a given report (identified by column number and title). To do so, access the Calculated Columnsform, a sub-level of both the Report Column Extensionform and the Expression/Condition (cont.)form.
  • Once you exit the Report Column Extension form, a check mark appears in the Expression/Condition column of the Report Columnsform. This flag helps you to spot any calculated columns in the report at a glance.

Displaying Alternative Date Formats

You can also use a calculated column to display dates in various formats. The default is MM/DD/YY (e.g., 01/22/92) in an American date format, or DD/MM/YY (e.g., 22/01/92) if you are using a European date format. The DTOA (Date to ASCII) expression is used to convert dates into another pattern (e.g., Fri, May-12-06; 12 May 2006). It is used as follows:
DTOA(table.column, ’pattern’)

Example: DTOA(ORDERS.CURDATE, ‘MMM DD, YYYY’) converts an order date of 07/12/06 to Jul 12, 2006 (in American format). The type of such a calculated column would be CHAR, and its width would be 12.


Note: For a list of available DTOA patterns, see ATOD and DTOA.


Condition for a Calculated Column

Sometimes you may wish to include a calculated column that has a condition. In that case, you do not create a calculated column, as described above. Instead, add a dummy column to the form (column name = DUMMY; table name = DUMMY) and assign itthe desired condition. The condition itself must be preceded by “=1 AND” or "= DUMMY.DUMMY AND".

Example: Column #131 in the ACCBYFNCPAT (Account Transactions by Type) report includes the following expression for DUMMY.DUMMY:
= 1 AND (FNCITEMS.DEBIT1 <> 0.0 OR FNCITEMS.CREDIT1 <> 0.0)

That is, the report only displays a sum when either DEBIT1 or CREDIT1 is greater or less than zero.

Conditions in a Group by Column

Suppose you want to create a report that displays the number of sales orders in a designated time period for each customer, but only for customers with more than a designated number of sales orders. In order to achieve this, you can specify a search condition (e.g., HAVING COUNT(*) > :MIN) for the group:

  1. Add a dummy column to the report (column name = DUMMY; table name = DUMMY).
  2. Hide the new report column.
  3. Indicate the function to be performed on the column (e.g., Col. Func. = S).
  4. In the Report Column Extension sub-level form, write an expression that represents the desired condition, using SQL syntax.

In the above example, you would record "= 0 AND COUNT(*) > :MIN", where :MIN is an input variable received by the procedure that executes the report.

If you then dump the report's query using the SQL Development (WINDBI) program, you will see that the SQL query now includes the following conditions in the GROUP BY clause:

HAVING SUM(DUMMY.DUMMY) = 0 
AND COUNT(*) &gt; :MIN 
AND (1 = 1)

Of course, the first and last conditions are always true.

Using a Complex Function

Sometimes you will want to perform a complex operation on a calculated column (beyond a simple sum, average, minimum or maximum).

Example: The TOTALTRANSBAL (Inventory Movement in Period) report includes a complex function in column #81 (Avg Monthly Consumption): (SUM(#56) / (#80))

Column #56 displays Outgoing Transact'ns, while column #80 calculates the number of months in inventory in the period.

Complex functions are defined (like all calculated columns) in the Report Column Extensionform. In addition, a Col. Func.of type Fmust be specified.

Further Reading