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Grouping

Type

Concept

Purpose

Grouping lets you process records with the same field value together.

Usage

There are two DQL operators that control grouping: in groups and in groups with group-totals. They perform identically; “in groups with group-totals” is included for compatibility with previous versions of DataEase.

The in groups operator causes records with identical values in a specified field to be processed as a single group. The groups are automatically sorted in ascending order. For example, French Polynesian clubs are listed together as a group followed by the Haitian clubs, and so on.

Example 1

for CLUBS ;

list records

COUNTRY in groups ;

CLUB NAME in order ;

CITY .

end

The output generated by the script in Example 1 is grouped on the COUNTRY field (shown in bold):

Example 2

The in groups operator groups records and generates statistical totals for each group if any other statistic is requested by the script.

for CLUBS ;

list records

COUNTRY in groups ;

CLUB NAME in order ;

CITY ;

"A" = "A" : count .

end

In this example, the count statistic allows DataEase to calculate the group total for each country. The line:

  "A" = "A" : count .

..tells DataEase to count every record that is processed.

The output includes the group level statistics (shown in bold):

There are two key points to remember when using Grouping:

Grouping automatically sorts groups in ascending alphabetical or numerical order (e.g., French Polynesian clubs before the Haitian clubs ).

Grouping operators must precede Sorting operators (in order and in reverse) in a script.