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所在平台: Udemy |
课程主页: https://www.udemy.com/course/sql-server-part3-advance-level/
课程评论：没有评论
**课程名称：SQL Server Part 3 - 高级进阶** **课程摘要：** 本课程将带您深入探索SQL Server中**联接（Joins）和高级查询**的奥秘。通过学习，您将能够： * **精通表关系与联接：** 掌握INNER JOIN、LEFT JOIN、RIGHT JOIN和FULL OUTER JOIN等联接类型，理解它们如何连接多个表的数据，并有效处理匹配与不匹配的记录。 * **理解真实场景中的嵌套联接与自联接：** 学习如何将表与其自身进行联接（自联接），以及如何使用嵌套联接处理多层级或历史数据中的复杂关系。 * **在联接中进行计算：** 了解如何在联接过程中对字段进行加、减或转换操作，从而创建更强大、更有意义的查询结果，例如计算相关行之间的差异。 * **使用UNION和UNION ALL合并数据集：** 学习如何将多个查询结果合并到一个输出中，并理解UNION（去除重复项）和UNION ALL（保留所有记录）的区别。 **课程亮点：** * **实用的联接案例：** 通过“获取客户订单（INNER JOIN）”和“显示所有客户，无论是否有订单（LEFT JOIN）”等迷你用例，深入理解联接在实际数据关联中的应用。 * **深入的技巧讲解：** 学习“自联接揭秘！”和“嵌套联接分步详解”，掌握如何通过自联接比较员工薪资与其经理，或通过嵌套联接跨越多于三张相关表查询数据。 * **对比分析：** 课程还将重点讲解“LEFT JOIN vs RIGHT JOIN：真实示例”，帮助您清晰区分不同联接类型的应用场景。 本课程旨在帮助您像专业人士一样链接表，轻松掌握SQL Server的高级查询技巧，应对更复杂的数据处理需求。
What You Will Learn from This Module on Joins and Advanced Querying:Master Table Relationships with JoinsLearn how INNER, LEFT, RIGHT, and FULL OUTER joins help you connect data across multiple tables and handle matching/non-matching records.Understand Real-World Scenarios with Nested and Self JoinsExplore how to join a table to itself (self join) and use nested joins to handle multi-step relationships-useful for hierarchy or historical data.Perform Calculations Within JoinsDiscover how to add, subtract, or transform fields during joins to create powerful and meaningful query results, such as calculating differences between related rows. Combine Data Sets with UNION and UNION ALLLearn how to merge results from multiple queries into a single output, understanding the difference between UNION (removes duplicates) and UNION ALL (keeps all records).Joins for Real-World Data LinkingMini Use-Case: Fetch customer orders by linking Customers and Orders using INNER JOIN, show all customers with or without orders using LEFT JOIN. "Joins Made Easy!""Link Tables Like a Pro" "LEFT vs RIGHT JOIN: Real Examples" Compare employee salaries with their managers using self join, or pull data across 3+ related tables using nested joins. "Self Join Demystified!" "Nested Joins: Step-by-Step" "Compare the Employees to Managers tables with SQL! "
