Download presentation
Presentation is loading. Please wait.
Published byGervais McCormick Modified over 9 years ago
1
SQL Unit – 2 Base Knowledge Presented By Mr. R.Aravindhan
2
SQL SQL is a standard language for accessing and manipulating databases.
3
What is SQL? SQL stands for Structured Query Language SQL lets you access and manipulate databases SQL is an ANSI (American National Standards Institute) standard
4
What Can SQL do? SQL can execute queries against a database SQL can retrieve data from a database SQL can insert records in a database SQL can update records in a database SQL can delete records from a database SQL can create new databases SQL can create new tables in a database
5
What Can SQL do? SQL can create stored procedures in a database SQL can create views in a database SQL can set permissions on tables, procedures, and views
6
SQL DML and DDL SQL can be divided into two parts: The Data Manipulation Language (DML) and the Data Definition Language (DDL).
7
DML The query and update commands form the DML part of SQL: SELECT - extracts data from a database UPDATE - updates data in a database DELETE - deletes data from a database INSERT INTO - inserts new data into a database
8
DDL CREATE DATABASE - creates a new database ALTER DATABASE - modifies a database CREATE TABLE - creates a new table ALTER TABLE - modifies a table DROP TABLE - deletes a table CREATE INDEX - creates an index (search key) DROP INDEX - deletes an index
9
SQL SELECT Statement Syntax SELECT column_name(s) FROM table_name Example SELECT LastName,FirstName FROM Persons
10
SQL SELECT DISTINCT Statement Syntax SELECT DISTINCT column_name(s) FROM table_name Example SELECT DISTINCT City FROM Persons
11
SQL WHERE Clause Syntax: SELECT column_name(s) FROM table_name WHERE column_name operator value Example: SELECT * FROM Persons WHERE City='Sandnes'
12
SQL ORDER BY Keyword Syntax: SELECT column_name(s) FROM table_name ORDER BY column_name(s) ASC|DESC Example: SELECT * FROM Persons ORDER BY LastName
13
SQL INSERT INTO Statement Syntax: INSERT INTO table_name VALUES (value1, value2, value3,...) Example: INSERT INTO Persons VALUES (4,'Nilsen', 'Johan', 'Bakken 2', 'Stavanger')
14
SQL UPDATE Statement Syntax: UPDATE table_name SET column1=value, column2=value2,... WHERE some_column=some_value Example: UPDATE Persons SET Address='Nissestien 67', City='Sandnes' WHERE LastName='Tjessem' AND FirstName='Jakob'
15
SQL DELETE Statement Syntax: DELETE FROM table_name WHERE some_column=some_value Example: DELETE FROM Persons WHERE LastName='Tjessem' AND FirstName='Jakob'
16
Thank You
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.