how to add additional column in query

Jul 26 2016 9:56 AM

i give the attachement given below .i want an additional column named as parentname.whoose parentid is greater than 0 will take the name of corresponding id field.

suppose if parrentid is 1 than it will take the id whoose id is 1 and their corresponding name is shown as their parentname for whose parent id is 1.