Postgresql – Select only duplicate values from the table
I need to select from a table (user_id, i_id) only those values that match both user_ids. Table structure: user_id i_id 713870562 2 713870562 3 713870562 4 713870562 5 713870562 6 713870562 7 713870562 8 713870562 9 22131245 6 22131245 7…