A method, database system, and computer program are disclosed for optimized costing. The method includes identifying a join that identifies a first table and a second table. The method further includes determining an optimized cost of reading the first table. If the number of unique first table values is greater than the number of unique second table values, the number of instances where a unique first table value matches a unique second table value is returned. Otherwise, the number of unique first table values is returned. The method further includes determining an optimized cost of reading the second table. The optimized cost of reading the second table includes the number of unique second table values. The method also includes summing the optimized cost of reading the first table and the optimized cost of reading the second table.