5 Joins

Question 1

joins

Answer 1

this will help in link 2 column together as one which came from different tables

Question 2

inner join

Answer 2

In inner join we get common colums from different tables

Question 3

syntax of inner join 1

Answer 3

select common column from common tables where table1.common column = table2.common column

Question 4

synatax of inner join 2

Answer 4

select common column from common table1 INNER JOIN common column 2 on table1.common column = table2.common column

Question 5

inner join return

Answer 5

this return common data in the table

Question 6

Outer join

Answer 6

this return un common data in the table

Question 7

Outer join Types

Answer 7

Left join, Right join , full join

Question 8

Left join, Right join , full join also called as

Answer 8

Left outer join, Right outer join , full outer join

Question 9

left join

Answer 9

This give more preference to first common column that comes after ON

Question 10

Right join

Answer 10

This give more preference to last common column that comes after ON

Question 11

Full join

Answer 11

If we want all uncommon data at single place.

Question 12

Union

Answer 12

stack one data on top of another table,

Question 13

union in null

Answer 13

this removes all duplicates

Question 14

Duplicates in union

Answer 14

The union also remove the duplicates

Question 15

union all

Answer 15

does not eliminate the duplicates even after specifying distinct

Question 16

Except

Answer 16

this takes result from 1st table and remove from 2nd table

Question 17

cartesian product

Answer 17

if we use no join

Question 18

Cross join

Answer 18

we use this when we use cartesian product

Question 19

View

Answer 19

virtual tabular form. This is generated using SQL query.

Question 20

insertion and deledtion of data in view

Answer 20

We cannot insert or delete data

Question 21

inline view

Answer 21

select * from ( select * from table)