The document discusses various Data Definition Language (DDL) commands in SQL such as CREATE, ALTER, and DROP for defining and modifying database structure. It explains how to create tables with columns, constraints, indexes and views. It also covers removing tables and altering table definitions by adding, modifying or dropping columns, constraints and indexes. Different database architectures like single, multi database and distributed databases are also summarized.

1. Creating a Database Chapter 13

6. Create table example create table classmaster ( classid varchar2(4) primary key, classname varchar2(15) not null unique, intake number(3));

7. Create table example Create table classmaster2 ( classid varchar2(4) , classname varchar2(15) not null , intake number(3), doa date default '01-JUL-10', primary key(classid), unique(classname), check (intake between 0 and 100), Constraint fk_clm_clname foreign key(classname) references classmaster(classname) ) ;

8. Create table example Create table studentmaster ( regno varchar2(4) primary key, classid varchar2(14) constraint fk_sm_clsmstr references classmaster(classid) on delete set null, sfname varchar2(20) not null, slname varchar2(20) not null, DOB date, DOA date default ’01-JUL-10’, AdmStatus char(1) check (admstatus in ('A','C','P')), freeship char(1) check (freeship in ('Y','N')), check( doa>dob)); );

36. THANKS