QlikView Data Files (QVD)

A QVD file is a very important feature in QlikView. It is a file containing a table of data exported from QlikView:

• QVD is a native QlikView format, meaning it can be read/write only from QlikView.

• Reading data from a QVD file is typically 10-100 times faster than reading from other data sources. It reduces the load on the database as QVDs can be loaded once and used multiple times without connecting to the database.

• QVD files can be shared easily among different applications.

• QVD files can combine data from multiple QlikView documents.

• An incremental load is implemented using QVD files.

• A QVD file consists of:

  • A well-formed XML header

  • Symbol tables in a byte stuffed format

  • Actual tables of data in a bit stuffed format

• QVD is created by using a STORE command.

Creating QVD files for our data model

We will store all the tables in the QVD files so that data read and write is faster:

1. Open QlikViewEssentials_Chap4_IntervalMatch.qvw and save as QlikViewEssentials_Chap4_QVDCreator...