In SQL What are the four data definition statements and what

In SQL...

What are the four \'data definition\' statements, and what do each of them do?

Solution

1.Create statement: it is utilized to establish a new table,database ,trigger and stored procedures..etc.this statement in SQL establishes a element in Relational database management system(RDMS).

syntax create table tablename;

Example create table employee

2.Drop statement: This drop statement damages the current table,trigger,view...etc in SQL it cleans the element from a relational database management system.dropping the objects is bsed on the utilization of RDBMS.

syntax Drop table tablename

Example Drop table employee

3.Alter statement: it is used to ADD,Delete,update columns in the existing table .After creating the table we can mate ant modifications in the structure of table.

syntax Alter table tablename

Example Create table tblemployee

Alter table tblproducts

4.Truncate statement:it deletes the total data in a table with quick perfomance because it dooesn\'t keep any log hence rollback is not possibleand also the where condition is not utilized .

syntax    Truncate Table Tablename

   Example Truncate Table Tblemployee