Storing intermediate data in the memory using tHashMap

While not strictly file based, there are alternative methods for storing intermediate data which are more efficient than using temporary files, so long as there is enough memory to hold the temporary data. This recipe shows how to do this using the tHashMap component.

Getting ready

Open the jo_cook_ch08_0040_temporaryDatatHashMap job. You will notice that this is the same job as in the previous recipe.

How to do it...

The steps for storing intermediate data in memory using tHashMap are as follows:

1. Delete the tCreateTemporaryfile component.

2. Replace the tFileOutputDelimited with a tHashInput component, having a generic schema of sc_cook_ch8_0040_genericCustomerOut.

3. Replace tFileInputDelimited with tHashInput component sc_cook_ch8_0040_genericCustomerOut.

4. Add the onSubjobOk link.

5. Run the job, and the results will be the same as for the previous recipe.

How it works...

tHashMap creates an in memory structure that holds all the data in the flow. It...