These Aggregate functions are aggregate functions as available on in stream views and pipes. Aggregate functions serve the purpose of aggregating data and giving it more eaningfull meaning. They are usually a common feature in any data based environment. In database management, for instance aggregate functions are used where multiple rows are grouped together to form a singe value or to find out more significant meaning, represented by a single value on a set of values.
Aggregate functions are also available on pipes and views in PhixFlow. The following composes a set of available functions:
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aggregate data, often grouped by other attributes, to give totals, max, min, avg values etc. for each key value, e.g. for each customer, region.
| Function | Description | ||||||||||||||||||||||
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| Average | This function returns the arithmetic average value of an attribute from records with the same key value. In detail, it returns the sum of all values for a key value, divided by the number of values that are not null. It is only available for numeric attributes. | ||||||||||||||||||||||
| Count | This function returns the number of non-null values of an attribute from records with the same key value. | ||||||||||||||||||||||
| Distinct | This function returns the number of unique values of an attribute from records with the same key value. | ||||||||||||||||||||||
| Maximum | This function returns the maximum value of an attribute from records with the same key value. It is available for numeric, string and date/time attributes. Strings are ordered alphabetically, with the shortest strings first. | ||||||||||||||||||||||
| Minimum | This function returns the minimum value of an attribute from records with the same key value. It is available for numeric, string and date/time attributes. Strings are ordered alphabetically, with the shortest strings first. | ||||||||||||||||||||||
| Percent | This function can be applied to a numeric field, to return the percentage of the sum of values for each key value in relation to the total sum of values. You should use this function in conjunction with one or more grouping attributes - each combination of values from these grouping attributes gives a key value. For example, you have a stream with 2 fields:
and you create a grid view:
This will give the view:
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| Sum | This function returns the sum of all values of an attribute from records with the same key value. It is only available for numeric attributes. |