The Complexity sheet ranks applications according to a complexity index, which can be controlled by the user.
The Application Complexity section lists all the QVWs found in the last scan and ranks them according to a complexity index that can be set by the user on the Complexity Chart Settings thresholds. The complexity value of a QVW is a sum of several different measures of complexity of a QVW's content.
The Complexity Index in the Complexity Breakdown for Scanned Applications table is based on settings for tables, fields, rows, number of sheets, and other factors. Each factor is an object that can be set by the user.
There are two settings to manage:
- Thresholds for the various factors can be set when the Complexity Indexes button is selected.
- Thresholds for highlighting the factors can be set when the Highlight Thresholds button is selected.
The purpose of several of the thresholds require explanation:
- Complexity Threshold: Set the Complexity level at which to highlight QVW names.
- Cardinality Threshold: Cardinality is a measure of uniqueness; the higher the percentage, the fewer tables, fields, and rows the QVW has in common with other QVWs.
- Calculated Dimensions: Indicates the number of calculations used to produce an object. The higher the number of calculated dimensions, the greater the processing required to construct the object.
- Set Analysis: Measures the use of sets in Expressions with aggregation functions in the QVW.
- Long Expressions: Indicates the number of expressions greater than 100 characters in length.
The measures in the Complexity Indexes are:
- Base is the level for factoring into the complexity index. If a QVW contains tables, sheets, or other objects whose counts are below the base settings, then those elements are not calculated in the complexity index. Any number that exceeds the base is used in the complexity index. For example, if the Tables Base is 5, and a QVW has 6 tables, then 1 would be used to calculate the complexity index.
- The Max value is used as a divisor in the complexity index calculation, so the higher the Max value, the lower the impact of counts that exceed the Base.
- The Weight is a multiplier in the complexity index calculation, so the higher the Weight, the greater impact of counts that exceed the Base.
Single QVW detail
The Single QVW Detail section allows you to select a QVW and analyze its key components:
- Objects, including variables
- Data Model
- Usage, including total sessions, total users, and number of times used during the last 14 and 90 days.
When QVWs show no data or no sheets, that could indicate those QVWs were created prior to QlikView 10. In that case, they should be upgraded to QlikView 11.
No data or no sheets can also indicate that the QVW is corrupted in some way and should be discarded.
The Tables and Fields table lists the tables and fields included in the QVW. It also includes Total Values for each field, which is the total number of values in a field, not unique values. The %Distinct field indicates the percentage of the total values that are unique values. A result of 100% means that all values are unique. 0% means that there are no unique values. The field contains only one value, or all the values are blank or null. Getting 0% distinct values is not common in fields with few Total Values, but with over a million Total Values, 0% can occur if there are very few unique value, for example, 10.
The File Size History line chart plots the QVW file size over time, based on each day the QVW is scanned.