Oracle SQL notes

ORACLE SQL



PRIYANKA

, SQL COMMANDS
 SQL(Structure Query Language) commands are instructions. It is used to communicate
database. It is used to perform specific tasks, functions and queries of data.

 There are several categories of SQL commands are as follows:-

1) Data Definition Language (DDL)
2) Data Manipulation Language (DML)
3) Data Control Language (DCL)
4) Transaction Control Language (TCL)
5) Data Retrieval Language (DRL)

, 1) DATA DEFINITION LANGUAGE (DDL)


DDL
 Data Definition Language, which defines
the structure or schema of the database. C 1. CREATE
 DDL commands are SQL commands used O
2. ALTER M
to modify or alter the structure of the
M 3. RENAME
database. A
 DDL commands are used to perform the 4. TRUNCATE N
D
following operation on table :- 5. DROP
S

, 1) DATA DEFINITION LANGUAGE (DDL)
1. CREATE


 To create a table in a database. EXAMPLE :

 Syntax:- SQL> create table Products
create table <tablename> (productid number(5),
( column1 datatype(size), productName varchar2(20));
column2 datatype(size),
………………………., output:-
column n datatype(size)); Table created.