DDL statements are used to build and modify the structure of tables and other objects in the database and A data manipulation language (DML) is a family of syntax elements similar to a computer programming language used for selecting, inserting, deleting and updating data in a database.

1. About Me
Md. Selim Hossain
Lecturer
Dept. of CSE
UTTARA UNIVERSITY
House#05, Section#06,
Road#15, Uttara, Dhaka-1230.
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2. Database
Management
System
(DBMS)
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3. Topics for Today
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4. Data Definition Language (DDL)
Data Manipulation Language
(DML)
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5. SQL statements are divided into two major
categories:
Data Definition Language (DDL) and
Data Manipulation Language (DML).
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6. Data Definition Language (DDL)
• DDL statements are used to build and modify
the structure of tables and other objects in
the database.
• DDL is a sub-language of SQL used to create
and manipulate objects in a database. DDL
provides the following statements to
manipulate the object in database:
CREATE, ALTER, DROP, TRUNCATE, RENAME
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7. Data Definition Language (DDL)
CREATE statement
(to create objects in the database):
• The CREATE statement in SQL creates a
component in a relational database
management system (RDBMS).
• The CREATE command is used to establish a
new database, table, index, or stored
procedure.
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8. CREATE TABLE statement
• A commonly used CREATE command is the
CREATE TABLE command. The typical usage is:
CREATE TABLE [table name] ( [column
definitions] ) [table parameters]
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9. CREATE TABLE statement
• An example of statement to create a table
named employees with a few columns is:
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10. CREATE TABLE statement
Note: The full structure of table can be viewed
with the DESC command.
DESC <TABLE_NAME>
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11. DROP statement
• The DROP statement destroys an existing
database, table, index, or view.
• A DROP statement in SQL removes a
component from a relational database
management system (RDBMS).
• Drop statement is used to delete an existing
object from the database. It can also be used
to delete any column from a table.
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12. DROP statement
• The DROP statement is distinct from the
DELETE and TRUNCATE statements, in that
DELETE and TRUNCATE do not remove the
table itself. For example, a DELETE statement
might delete some (or all) data from a table
while leaving the table itself in the database,
whereas a DROP statement removes the
entire table from the database.
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13. DROP statement
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14. DROP statement
The typical usage is simply:
• For example, the command to drop a table
named employees is:
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15. ALTER statement
• The ALTER statement modifies an existing
database object or, Alter statement is used to
modify the structure of an existing object.
• Below alteration can be done on a table:
o Addition of new columns
o Deletion of existing columns
o Changing the data type of columns
o Changing the size of columns
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16. ALTER statement
• The typical usage is:
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17. ALTER statement
Note: To change the data type of a column,
the column must be empty.
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18. RENAME statement
Rename statement is used to rename an
existing object from a database
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19. RENAME statement
• The RENAME statement is used to rename a
database table.
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20. TRUNCATE statement
• The TRUNCATE statement is used to delete all
data from a table. It's much faster than
DELETE.
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21. Data Manipulation Language (DML)
• A data manipulation language (DML) is a
family of syntax elements similar to a
computer programming language used for
selecting, inserting, deleting and updating
data in a database.
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22. Data Manipulation Language (DML)
 DML also known as query language
Two classes of languages
 Procedural – user specifies what data is
required and how to get those data
 Nonprocedural – user specifies what data is
required without specifying how to get
those data
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23. Data Manipulation Language (DML)
• DML is a sub-language of SQL. It is used to
manipulate the data stored in a table.
• DML provides the following statements for
data manipulation:
INSERT
UPDATE
DELETE
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24. Data Manipulation Language (DML)
INSERT Statement
• INSERT statement is used to insert a new
record into a table.
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25. Data Manipulation Language (DML)
INSERT Statement
• Example
• Consider a table 'EMP' having columns
named EMPNO, NAME, SAL and JOB. We can
be used the below INSERT statement to insert
a new record to it.
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26. UPDATE Statement
• Update statement is used to update an
existing record in a table.
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27. UPDATE Statement
• If the where clause of omitted, the statement
will update all the values in the particular
column.
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28. UPDATE Statement
• Note: IS NULL is used for assignment and =NULL
is used to recognize.
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29. DELETE Statement
• Delete Statement is used to delete records from
a table.
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30. DELETE Statement
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31. DELETE Statement
• Below statement will delete all records from
the table.
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32. Md. Selim Hossain
Thank you
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