In this type of extraction, all the data from the source system is pulled using the extraction scripts. It is like creating replica of the required tables from the database in the staging area. The advantage of full load is that you do not need to worry about any changes happening in the source database, such as insert, update, or delete. Every time you extract the data, you pull the entire data from the source, and thus don't miss any data since the last extraction.

This process allows hassle free scripting, as there is no need to apply any logic while pulling the data. But on the other hand, it is a time-consuming process due to the full extracts of the data. The time required to finish the extraction process depends on the numbers of records and fields a particular table has.

Let us understand the concept using an example. Let us assume that you want to do a full load on sales table. A sales table with data is shown in the following image:

Assuming that the preceding data is stored in excel named Sales.xlsx, the full load script in Qlik Sense will be as follows:

Once this script is reloaded, it will fetch the nine records. Now if new data gets added, modified, or deleted in the table, the same script will be used to get the entire data. Every time the script is reloaded, it will purge the old data which is already fetched and extract full data from the source system and store it in QVD.