Relational algebra has its treats. One of the most academic features is the relational division. It is hardly ever used, but comes in handy every now and then. And when you need it, you'll probably hate yourself for having slept during the relevant classes at the university. What is relational division? Relational division is the … Continue reading Advanced SQL: Relational division in jOOQ
Tag: language sql
SQL incompatibilities: NOT IN and NULL values
This is something where many hours of debugging have been spent in the lives of many SQL developers. The various situations where you can have NULL values in NOT IN predicates and anti-joins. Here's a typical situation: with data as ( select 1 as id from dual union all select 2 as id from dual … Continue reading SQL incompatibilities: NOT IN and NULL values