Here is something for the people that are working with SSIS packages on a daily basis.

 If you ever worked on creating SSIS package programatically, maybe you searched how to solve the problem of adding parameter (SSIS variable) to an OLE DB source (not to sql task (!)) used with sql command. For example, your OLE DB source sql command is SELECT * FROM Production.Product WHERE product_type = ?

Of course, ? means parameter, and you want to add a prameter to an OLE DB source.I've searched alot for the answer, but, though there are lots of explanations and examples on the Internet about this topic, still I did not find answer to this one.

The answer is to get the GUID of the package variable which value you want to assign to be parameter value, and then to set OLE DB ComponentProperty("ParameterMapping", @"""ParamName""" + "," + StringThatContainsVariableGUID + ";"); And that's it! Hope someone will have to search less for this answer now.