Talend enabling (unhiding) and using tHashinput and tHashoutput components

Talend tHashinput and tHashoutput (in memory data components) :

Talend provides tHash* components for storing data in memory hash. You can fetch data from any input component and store it in memory using tHashoutput. Later you can use tHashinput to read from any linked tHashoutput component and do your transformation/processing on data.

Enabling tHash* - by default these components are hidden in talend open studio (atleast till ver 5.3) To enable these go to File Menu-->Edit project properties-->PaletteSettings.
Here you can see components inside their folders - Technical is the folder which contains tHash* components. You can make this folder or components visible by bringing them to Show section of dialogbox and applying changes. I have brought tHashInput and tHashoutput to show section below.



Job below generate sample data for city code and name and then stores it in tHashoutput and next fetches this data using tHashinput and transforms this data by combining city code+city name


tHashoutput has a schema and same should be the schema for tHashinput
tHashoutput setting - you can link new tHashoutput to existing tHashoutput and append data.