What is a join?Explain the different types of joins?




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What is a join?Explain the different types of joins?..

Answer / sheels

Join is used to combin rows from multiple table. Join is performed when ever two or more table is listed in the FROM clause of an SQL statment.
Types of Join;
1.Natural Join: Natural join tells the database to join two table using the common columns.
2.Equality Join: Here the table is related using the equal(=) sign.
3.Inner Join: This is the most common type of join. Inner join returns all the rows from the table when the join condition is met.
4.Outer Join:It joins the matching records from two table and all the records from one side of the table and those un matching records have null value.
(i)Left Outer Join:It joins the matching records from two table and all the records from left side of the table and those unmatching records have null value.
(ii)Right Outer Join: It joins the matching records from two table and all the records from right side of the table and those unmatching records will have null value
5.Self Join: It is used to join a table to it.

Is This Answer Correct ?    24 Yes 0 No

What is a join?Explain the different types of joins?..

Answer / pratap

Joins are the methods used to access related data from one
or more tables. there are five types of join
1. Equi join(i.e. Inner join)
2. self join
3. left join
4. right join
5. outer join

Is This Answer Correct ?    17 Yes 6 No

What is a join?Explain the different types of joins?..

Answer / sandeep verma

Join match/combine two or more tables from a database. It means, combining rows or fields of two or more tables matching the common values. There are various types of joins which are as follows:
a) Self Join: joining table with it's own record to extract unique record (one employee is manager of other two employee)
b) Inner Join
i) Equi Join:No difference with inner join (just write join instead of inner join)
ii) Cross Join: will get you result each row of first table with each row of the other table(i.e. select * from employee cross join salary)
c) Outer Join
i) Left Outer Join:joins the matching records from two tables and all the records from left side of the table and those unmatched records have null value in right side of the table.
ii) Right Outer Join:joins the matching records from two tables and all the records from right side of the table and those unmatched records have null value in left side of the table.
iii) Full Outer Join: Regardless of matching record of both side of the tables, it produce all the records of both the table and produce NULL values for every column of the table that lacks of matching row.

Is This Answer Correct ?    4 Yes 0 No




What is a join?Explain the different types of joins?..

Answer / lakshminarayana reddy

used to retrieve desired data from more than 1 table we use
join.
joins types:- 1.Equi join
2.non-Equi join
3.outer join
4.Self join

Is This Answer Correct ?    10 Yes 7 No

What is a join?Explain the different types of joins?..

Answer / thilaga

inner, outer join,natural join. link between togther

Is This Answer Correct ?    0 Yes 1 No

What is a join?Explain the different types of joins?..

Answer / pravin

Joins are the methods used to access related data from one
or more tables. there are five types of join
1. Inner Join
2. Outer Join
3. Self Join
4. Mix Join
5. Exception Join

Is This Answer Correct ?    12 Yes 18 No

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