Uniq (Unix like)

The Uniq generation rule allows to perform a search for unique value from a list of ordered values. It performs like a uniq command on Unix systems.

For example, from a source list of values such as A,A,B,B,B,C,D it will produce A,B,C,D.

But if source values are not ordered you can end with duplicates in the generated values. For example, if you apply a Uniq rule on a source providing a sequence such as A,B,A,B,C,C,D,D the you wil have A,B,A,B,C,D

If your source values are not ordered you can still use Sort generation rule to order them.

It is also possible to produce each unique value with the number of occurences of that value. This is just like using 'uniq -c'.

To configure that rule you need to define two children, the one providing the source value to search unique from and another child wich provide the unique key. Usually the key is just a copy of the value but you can make any processing on the source value like extracting / transforming a subset of the source value.

Notice that the Uniq generation rule produces

Example: You can count the number of source records that have a specific value for one of the fields.

It works also just like a select count()  group by ...

Add comment

Security code