Qlikview 11 for developers - optimizing loading from QVD
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The Exists() function takes two parameters:
WHERE Exists([%Aircraft Type ID], AC_TYPEID);
Where Exists([%Aircraft Type ID]);
Depending on how the field names from the input table are defined, we should use the appropriate syntax from the two presented above. The main advantage of the second scenario (one-parameter syntax) is that, when loading from a QVD, it will still perform as an optimized load, while the first scenario will not.
What does this mean - an optimized load ? How id scenario 2 better ?
Optimizing means that your app is fully utilizing the QlikView compression algorithm used for efficiently storing data in-memory. When you reload the app you will see 'optimized' appear against the files that it is reading in. Consequently, storing and extracting optimized data can be much , much faster than non-optimized data.
To summarize - the more optimized your app is, the faster it will process data.
