//:playground
var query = new Query("Comments")
.Select("PostId")
.SelectRaw("count(1) as count")
.GroupBy("PostId");
SELECT [PostId], count(1) as count FROM [Comments] GROUP BY [PostId]
//:playground
var query = new Query("Companies")
.Select("Profit")
.SelectRaw("COUNT(*) as count")
.GroupByRaw("Profit WITH ROLLUP");
In PostgreSql
SELECT "Profit", COUNT(*) as count FROM "Companies" GROUP BY Profit WITH ROLLUP