This document outlines a performance benchmark on selecting all values from a larger table, joined by a smaller table, where no joined values exists. In other words, an inverted INNER JOIN clause. It ...

This document outlines performance on using NOT IN versus NOT EXISTS clauses, where the compared field is NULLABLE or not NULLABLE. If your fields are not nullable, it does not make a difference. If ...

生徒が1人以上いるクラスを取得(2年B組は除外される) SELECT * FROM classes c WHERE EXISTS ( SELECT * FROM students s WHERE s.class_id = c.class_id ); 3．上記2．でYESになったので結果に含める 4．classesテーブルの次の行を取得し上記の手順で調べる 5．同じようにclassesテーブルの ...

This article discusses the “DROP IF EXISTS” statement available in SQL Server 2016 and later versions. “IF EXITS” is the latest optional clause added in the existing DROP statement in SQL Server 2016 ...