The document provides an overview of basic SQL commands categorized into DDL, DML, DCL, and TCL. It includes syntax examples for creating, modifying, and deleting tables, as well as data manipulation techniques such as selecting, inserting, updating, and deleting records. Additionally, it explains the use of joins to combine rows from different tables and highlights aggregate and scalar functions.

1. Basic SQL COMMANDS
MUHAMMED MASHAHIL P
ASSISTANT PROFESSOR
CAS VAZHAKKAD

2. Sqlstatements
• Query or command to perform atask ina
database
4 type
1. DDL
2. DML
3. DCL
4. TCL

3. DDL
Data definitionlanguage
• Create
• Alter
• Drop
• truncate

4. Create
Syntax in mysql
CREATETABLEtable_name
(
column_name1 data_type(size), column_name2 data_type(size),
....
);Example
create table tbl_stock (
pk_int_stock_id int auto_increment, vchr_name varchar(20),
int_quantity int,
int_price int,
primary key(pk_int_stock_id)
);

5. Alter
Syntax inmysql
Alter table table_name modifycolumn
column_name data_type;
Example
alter table tbl_stock modify columnint_price
float;

6. Drop
Syntax inmysql
Drop table table_name;
Example
Drop table tbl_student;

7. Truncate
Syntax inmysql
Truncate table table_name;
Example
Truncate table tbl_student;

8. DML
Data manipulationlanguage
• Select
• Insert
• Update
• delete

9. Select
Syntax inmysql
Select * from table_name;
Example
Select * from tbl_stock;

10. Insert
Syntax inmysql
insert into table_namevalues
( );
Example
insert into tbl_stockvalues
(NULL,"mouse",10,500,1);

11. Update
Syntax inmysql
Update table_name set column_name=
Example
• update tbl_stock set int_price=int_price+1.50;

12. delete
Syntax inmysql
Delete from table_name;
Example
Delete from tbl_stock;
Difference between delete andtruncate??

13. DCL
Data control language
• Grant
• Revoke

14. Grant
Syntax inmysql
GRANTprivilege_type ONtable_name TO
‘user_name'@'localhost';
Example
GRANTselect ONtbl_supplier TO
'john'@'localhost';

15. Revoke
Syntax inmysql
REVOKEprivilege_type ONtable_name FROM
‘user_name'@'localhost';
Example
REVOKEselect ONtbl_supplier FROM
'suhail'@'localhost';

16. TCL
TransactionControl language
• Commit
• rollback

17. functions
• Built in function-perform calculation ondata
1. Aggregate function
2. Scalarfunction

18. Aggregatefunction
• Return asingle value for all the values inthe
column after calculation
AVG()
Mysql syntax
Select avg(coulmn_name) from table_name;
Example
Select avg(int_salary) from employee;
COUNT(),FIRST(),LAST(),MAX(),MIN(),SUM()

19. Groupby
• Togroup the result set by one or morecolumn
• Often used in conjunction with aggregate
function
Syntax in mysql
SELECTcolumn_name, aggregate_function(column_name)
FROMtable_name
GROUPBYcolumn_name;
Example
Select vchr_city,sum(mark) from tbl_student group byvchr_city;

20. Scalarfunction
• Return single value for eachvalue in acolumn
UCASE()
Syntax in mysql
Select UCASE(column_name) fromtable_name;
Example
Select UCASE(first_name) from tbl_student;
• LCASE(),MID(),LEN(),ROUND(),NOW(),FORMAT()

21. Joins
• Usedto combine rows from two or more
tables
Different joins
• inner join
• Left join
• Right join

22. Innerjoin
• Returns all rows when there is at leastone
match in BOTHtables
Syntax in mysql
Select column_name(s) from table1 join table2on
table1.column_name=table2.column_name;

23. Pk_int_dept_id Vchr_dept_name
1 CS
2 EC
3 EE
4 MECH
pk_int_class_id Vchr_class_name int_dept_id
1 CS100 1
2 CC300 5
3 EC100 2
4 MECH100 4
Example
select vchr_dept_name,vchr_class_name,pk_int_dept_id,int_dept_id from
tbl_dept join tbl_classes ontbl_dept.pk_int_dept_id=tbl_classes.int_dept_id;

24. Theresult setwill be
Vchr_departmen
t_ name
Vchr_class_name Pk_int_dept_id int_dept_id
CS CS100 1 1
EC EC100 2 2
MECH MECH100 4 4

25. Leftjoin
• returns all rows from the left table (table1), with the matching
rows in the right table(table2).
• Syntax inmysql
SELECTcolumn_name(s)
FROMtable1
LEFTJOINtable2
ONtable1.column_name=table2.column_name;

26. Pk_int_dept_id Vchr_dept_name
1 CS
2 EC
3 EE
4 MECH
Pk_int_class_id Vchr_class_name int_dept_id
1 CS100 1
2 EC100 2
3 CC100 5
4 MECH100 4
select vchr_dept_name,vchr_class_name,pk_int_dept_id,int_dept_id from
tbl_dept LEFTjoin tbl_classes on
tbl_dept.pk_int_dept_id=tbl_classes.int_dept_id;

27. Theresult will be
Vchr_dept_na
me
Vchr_class_na
me
Pk_int_dept_i
d
int_dept_id
CS CS100 1 1
EC EC100 2 2
EE NULL 3 NULL
MECH MECH100 4 4

28. Rightjoin
• Return all rows from the right table, and the matched rows from the left
table
Syntax in mysql
SELECTcolumn_name(s)
FROMtable1
RIGHTJOINtable2
ONtable1.column_name=table2.column_name;

29. Pk_int_dept_id Vchr_dept_name
1 CS
2 EC
3 EE
4 MECH
Pk_int_class_id Vchr_class_name int_dept_name
1 CS100 1
2 EC100 2
4 MECH100 4
select vchr_dept_name,vchr_class_name,pk_int_dept_id,int_dept_id from
tbl_dept RIGHTjoin tbl_classes on
tbl_dept.pk_int_dept_id=tbl_classes.int_dept_id;

30. Theresult will be
Vchr_dept_na
me
Vchr_class_na
me
Pk_int_dept_i
d
int_dept_id
CS CS100 1 1
EC EC100 2 2
MECH MECH100 4 4
NULL CC100 NULL 5

31. Thankyou