QlikView Reference Manual.pdf - QlikCommunity - QlikView

The complexity of the actual solution depends on the nature of the source database, but the following basic
cases can be identified:
1) Case 1: Append Only (page 395) (Log files).
2) Case 2: Insert Only (No Update or Delete) (page 396) (No Update or Delete).
3) Case 3: Insert and Update (No Delete) (page 397) (No Delete).
4) Case 4: Insert, Update and Delete (page 398).
Below you will find outlined solutions for each of these cases. The reading of QVD files can be done in
either "super-fast mode" or "standard mode". (The method employed is automatically selected by the Qlik-
View script engine depending on the complexity of the operation.) "super-fast mode" is (very approximately)
about 10x faster than "standard mode" or about 100x faster than loading the database in the ordinary fashion.
Case 1: Append Only
The simplest case is the one of log files, which are only appended. The following conditions apply:
l The database must be a log file which is contained in a text file (no ODBC/OLE DB).
l QlikView keeps track of the number of records that have been previously read and loads only records added at the end
of the file.
395