SQL 面接の質問と回答
Question: What is a join? Explain the different types of joins?Answer: Join is a query, which retrieves related columns or rows from multiple tables.Self Join - Joining the table with itself. Equi Join - Joining two tables by equating two common columns. Non-Equi Join - Joining two tables by equating two common columns. Outer Join - Joining two tables in such a way that query can also retrieve rows that do not have corresponding join value in the other table. |
復習用に保存
この項目をブックマークに追加したり、難しい内容としてマークしたり、復習セットに入れたりできます。
役に立ちましたか? はい いいえ
ユーザー評価で最も役立つ内容: