Understanding SIFT tables
SIFT stands for Sum Index Field Technology and is used by NAV to keep track of data to quickly perform complex calculations. This recipe will show you how they work.
How to do it...
Design Table 379, Detailed Cust. Ledg. Entry.
Click on View | Keys from the menu.
View the Properties for some of the enabled keys. You will notice one property called
MaintainSIFTIndex. This is the property that tells SQL Server to store the totals of the SumIndexFields.
How it works...
Prior to NAV 5.0 SP1, SIFT values were stored in actual tables. In later versions, they earned the nickname VSIFT because they are stored as views. This explanation will focus on VSIFT, but for a deeper description of SIFT and how it works, check out Jörg A. Stryk's book, The NAV/SQL Performance Field Guide.
We will take a look at the key Customer No., Initial Entry Due Date, Posting Date. This is the fourth key in the list (if you start with 0 as the first key). The view that will be created for this key...
