How to aggregate one column with respect to another

[Cerin]

I have a large spreadsheet with two columns, “ID”, and “Name”. Is there a function in LibreCalc to tell me which values of ID correspond to more than one unique name?

In SQL, this would be SELECT name, COUNT(DISTINCT name) AS name_count FROM table GROUP BY name HAVING name_count > 1;, but I’d like to avoid having to setup a SQL database just to perform this check.

[mahfiaz]

If I get you right you just want to make sure all the names are unique. In a third column do =COUNTIF($B$1:$B$1000; B1), every row where count is > 1 has a duplicate.

So on which row the duplicate is? In the fourth column do something like this: =IF(C1>1;MATCH(B1;$B2:$B$1000;0)+ROW(B2)-1;"")