The Hash transformation creates a nearly unique string representing a 64-bit number from the input values.
This transformation provides the same hash value when given the same inputs.
The resulting value is nearly unique because the transformation uses a 64-bit number as the space of possible hash values. For one million unique inputs to the hash transformation, there is a 1 in 38,000,000 chance of getting a duplicate hash value.
|Name||Descriptive name of the transformation. You can enter any name here.|
|Comments||Optional. Notes about the transformation.|
|Condition||The conditions under which this transformation is applied.|
|Default||The default value to use if the input value is not available.|
|Inputs||The set of inputs to use to create the hash value.|
|Output||The name of the field for output.|
In this example, the values of the c-ip and cs(user-agent) fields are used to create a tracking ID, which is stored in the x-trackingid field.
This example does not represent an ideal solution for creating unique tracking IDs. However, in situations in which archival log information is used, it may be the best method.