Database - What is a join and explain different types of joins
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What is a join and explain different types of joins. - Joins are used in queries to explain how different tables are related.
- Joins also let you select data from a table depending upon data from another table.
Types of joins: INNER JOINs, OUTER JOINs, CROSS JOINs.
OUTER JOINs are further classified as LEFT OUTER JOINS, RIGHT OUTER JOINS and FULL OUTER JOINS. What is a join and explain different types of joins.- Joins are utilized to get the results from two or more tables. There are two types of joins available.
1. Outer Join: Outer join has two categories – left outer join and right outer join. In this join functionality, two or more tables are joined by including blank rows in the specified side, once the criterion satisfies.
- The combination of left outer join and right outer join is simple outer join.
2. Inner Join: In this join functionality, two or more tables are joined by leaving the blank rows for checking.
- Other than these two joins, there are-
Natural Join: This join is the Cartesian product.
Equi Join: A condition includes an operator
NonEqui Join: They are conditional joins which does not use their conditions.
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25 RDBMS Interview Questions and Answers - Freshers, ExperiencedRDBMS interview questions and answers for freshers and experienced - List of RDBMS questions with answers that might be asked during an interview - Why a database is called as relational database model?, What are entities and attributes referring to?, What do you understand by relation in relational database model?
