Most important MySQL Keywords and their Description.

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Most used Keywords in MySQL

S.No

Keywords

Description

1

ADD

Add’s columns to the existing table.

2

ALTER

Modifies columns in the table and changes the  data type of column

3

ANY

Return’s True (or)False, if any subquery meets the condition

4

AS

Used for aliasing

5

BETWEEN

Selects values on a  given range

6

COLUMN

Changes the  data type of column or delete column

7

CREATE DATABASE

Creates a database

8

CREATE INDEX

Creates index for all the rows including duplicate values 

9

CREATE UNIQUE INDEX

Creates index for all the rows excluding duplicate values 

10

DISTINCT

Selects different/unique values in the column

11

DROP COLUMN

Deletes the column

12

DROP INDEX

Deletes Index column

13

DROP TABLE

Deletes table from the database

14

FOREIGN KEY

Constraint used to link two tables

15

FROM 

Specifies/Locates the table 

16

FULL JOIN

Return all the records where there is a match in either the  left (or) right table

17

GROUP BY

Groups the results based on column (used with aggregate function)

18

HAVING

Used instead of WHERE clause, since WHERE clause cannot deal with aggregate functions

19

IN

Specifies multiple columns in WHERE clause

20

INNER JOIN

Joins two tables with matching values in both tables

21

INSERT INTO SELECT

Copies data from one table to another table 

22

IS NULL

Tests empty values

23

IS NOT NULL

Tests non-empty values

24

LIKE

Searches for a specific pattern in the column

25

LIMIT

Specifies the number of records to be shown in the result

26

NOT

Only includes rows where the  condition is not true 

27

NOT NULL

Enforces columns, not to accept null values 

28

ORDER BY

Sorts the result

29

OUTER JOIN

Returns all rows where there is a  match in either left (or) right tables 

30

PRIMARY KEY

Unique identifier

31

RIGHT JOIN

Returns all rows from the right table and matching rows from the left table

32

TRUNCATE TABLE

Deletes data from the table(table will remain, data will be deleted)

33

UNION

Combines the result set of two or more select statements(only unique values)

34

UNION ALL

Combines the result set of two or more select statements(allows duplicates values)

35

WHERE

Filters the result


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