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If you are a programmer, do you know how many types of SQL Joins there are?

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  • 工作学习 / 学科技术讨论 / If you are a programmer, do you know how many types of SQL Joins there are?
    • A programmer should know 3 types of joins: nested loop join, sort-merge join and hash join.
      • Oops! I know none of them! :(
        • this join is not that join :-)
    • inner join, left join, right join.
    • 一般key都是不null的,所以简化一下就是4种
    • 就我的理解有三种:Inner (包括Self-Join), Outer (Full, Left, Right), 及 Cross Join (无需 JOIN 条件)