dynamic variable in Pentaho

Question

Suppose, I have set multiple variables in pentaho with values like following picture:

enter image description here

I have set it in global variable like : $YYYYMMDD:DD-1, $YYYYMM00:DD-1,...

Now, I have a table named 'xyz' with var_item column having records like:

enter image description here

How do I set value of those variables to records of var_item column, then insert those values to new column in 'xyz' table ?

The result I expecting like following pic:

enter image description here

• nbk: please read meta.stackoverflow.com/questions/285551/… and edit your question
• Omegad: When you talk about "variable", do you mean "Parameters", from a transformation ? Can you please be more specific on the data you have and the result you want from it ? (You want to join a table ? From SQL ?)