I am looking to create a group indicator for a query using SQL (Oracle specifically). Basically, I am looking for duplicate entries for certain columns and while I can find those what I also want is some kind of indicator to say what rows the duplicates are from. Below is an example of what I am looking to do (looking for duplicates on Name, Zip, Phone). The rows with Name = aaa are all in the same group, bb are not, and c are. Is there even a way to do this? I was thinking something with OVER (PARTITION BY ... but I can't think of a way to only increment for each group. +----------+---------+-----------+------------+-----------+-----------+ | Name | Zip | Phone | Amount | Duplicate | Group | +----------+---------+-----------+------------+-----------+-----------+ | aaa | 1234 | 5555555 | 500 | X | 1 | | aaa | 1234 | 5555555 | 285 | X | 1 | | bb | 545 | 6666666 | 358 | | 2 | | bb | 686 | 7777777 | 898 | | 3 | | aaa | 1234 | 5555555 | 550 | X | 1 | | c | 5555 | 8888888 | 234 | X | 4 | | c | 5555 | 8888888 | 999 | X | 4 | | c | 5555 | 8888888 | 230 | X | 4 | +----------+---------+-----------+------------+-----------+-----------+