8 Matching Annotations
  1. Last 7 days
  2. Apr 2020
    1. Joins are not expensive. Who said it to you? As basically the whole concept of relational databases revolve around joins (from a practical point of view), these product are very good at joining. The normal way of thinking is starting with properly normalized structures and going into fancy denormalizations and similar stuff when the performance really needs it on the reading side. JSON(B) and hstore (and EAV) are good for data with unknown structure.
  3. Mar 2020
  4. Jan 2020
    1. The SELECT part should not contain any columns not referenced in GROUP BY clause, unless it is wrapped with an aggregate function.
    1. Which to use? ANY is a later, more versatile addition, it can be combined with any binary operator returning a boolean value. IN burns down to a special case of ANY. In fact, its second form is rewritten internally: IN is rewritten with = ANY NOT IN is rewritten with <> ALL