DML COMMANDS

DML : Data manipulation commands are used to manage data in a record which can be manipulated using some query as

1:INSERT
2:UPDATE
3:DELETE
4:SELECT

INSERT COMMAND : Insert command is used to insert values in a table :
Syntax :

INSERT into table-name Values( data1, data2, data3, ……………. );

or

INSERT into table-name Values(&ATR1,&ATR2,&ATR3,………..);

Where ATR1,ATR2,ATR3……. are the attribute of table.

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Delete commands : Used to delete all records from the table or a particular row from a table :

Syntax :

DELETE from table-name;

or

DELETE from table-name WHERE condition;

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UPDATE COMMAND : – Used to update data of a row in a record:

Syntax :

UPDATE table-name SET column-name = ‘value’ WHERE condition;

For Multiple values –

UPDATE table-name SET column1-name = ‘value’,column2-name = ‘value’ WHERE condition;

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SELECT QUERY :-

Use to fetch data to display unit from database:  It can retrieve data from database and view it as temporary level :

Syntax :  to view all records

SELECT * from table-name

to view individual columns –

SELECT column1,column2,columnN from table-name

to view records based on condition :

SELECT * from table-name WHERE condition

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EXAMPLES

Table 1 : T1

Name

Id

Address

INSERT into T1 Values(‘Sherlock’,’205’,’221b’ );
INSERT into T1 Values(‘Jhon’,’305’,’221b’ );
INSERT into T1 Values(‘Lestrade’,’405’,’DI12’ );
INSERT into T1 Values(‘Molly’,’505’,’B_House’ );

Name	Id	Address
Sherlock	205	221b
Jhon	305	221b
Lestrade	405	DI12
Molly	505	B_House

DELETE from T1 WHERE Id=’405’;

Name	Id	Address
Sherlock	205	221b
Jhon	305	221b
Molly	505	B_House

UPDATE T1 SET Id= ‘105’ WHERE Name=’Sherlock’;

Name	Id	Address
Sherlock	105	221b
Jhon	305	221b
Molly	505	B_House

SELECT * from T1 WHERE Id=’105’;

 

Name	Id	Address
Sherlock	105	221b