SumIndexFields let you quickly calculate the sums of numeric columns in tables, even in tables with thousands of records. SumIndexFields are the basis for the FlowFields in a C/SIDE application. This section describes how SumIndexField Technology (SIFT) works on Classic Database Server as well as how SIFT is implemented in Microsoft Dynamics NAV with Microsoft SQL Server. This information will help programmers develop efficient applications that use SumIndexField Technology.
SIFT
SIFT has been designed to improve performance when implementing such activities as calculating customer balances. In a traditional database system this involves performing a series of database calls and calculations before arriving at a result. The power and efficiency of SIFT on Classic Database Server makes calculating sums for numeric columns in tables very efficient, even in tables that contain thousands of records. This powerful feature is used throughout the Microsoft Dynamics NAV application in both database options.
SumIndexFields
A SumIndexField is associated with a key in the table. Each key can have up to 20 associated SumIndexFields. When you design your database, you can associate a decimal field with a key as a SumIndexField. This tells the Database Management System (DBMS) to create and maintain a structure that contains the accumulated sum of the values in a column. When a user selects a new key, any SumIndexFields associated with that key become accessible.