COMPUTER SCIENCE AND ENGINEERING
SQL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Left Join
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Right Join
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Cross Join
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Inner Join
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Detailed explanation-1: -Hash joins are also a type of joins which are used to join large tables or in an instance where the user wants most of the joined table rows.
Detailed explanation-2: -The maximum number of tables that can be referenced in a single join is 61. This also applies to the number of tables that can be referenced in the definition of a view.
Detailed explanation-3: -When to use the CROSS JOIN? The CROSS JOIN query in SQL is used to generate all combinations of records in two tables. For example, you have two columns: size and color, and you need a result set to display all the possible paired combinations of those-that’s where the CROSS JOIN will come in handy.
Detailed explanation-4: -LEFT OUTER JOIN-You get all rows from the left table, plus rows from the right table, where they match the left. RIGHT OUTER JOIN-Opposite of Left Join (Rarely used). CROSS JOIN-Joins all rows in both table. If both tables have 10 rows, you’ll get 100 rows back.