How to Troubleshoot Apps for the Modern Connected Worker
jdbc
1. SARDAR PATEL INSTITUTE OF
TECHNOLOGY AND MANAGEMENT
MANDLESHWAR
Submitted To
Proff.Aashutosh Yadav
Prepared by-:
Gayatri Patel
Enroll No.0881CS101009
CSE-Final year
4. JDBC – J ava D ata B ase C onnectivity
JDBC is a Java API that enables java program to
execute SQL Statements.
The JDBC API can also be used to interact with
multiple data sources in a distributed ,
heterogeneous environment.
7. JDBC – ODBC Bridge (Type 1)
Java
Application
ODBC
Layer
JDBC
API
Database
JDBC
ODBC Drivers
ODBC
API
Function –
Translate JDBC call to ODBC calls and send them to the ODBC database.
It is a java Wrapper developed over ODBC API.
Advantages - 1. Easily available as part of JDK
2. Easy to install.
Disadvantages- 1. slower in performance.
2. Limited to functionality of ODBC driver.
3. Not Recommended for production environment.
8. Native-API partly Java Driver(Type2)
Java
Application
JDBC
API
Vendor API
Database
JDBC Driver
Written partly in java & partly in native code.
It uses a mixture of Java implementation and vendor-specific native API’s to
provide data
access.
Uses native ‘c’ language lib calls for conversion.
Advantage – these offer better performance than jdbc-odbc bridge as layers are
less and it uses Native API which is database specific.
Disadvantage – not fully in java so portability issue , if database is changed than
native API must be changed as it is database specific.
9. Network Protocol All-Java Driver(type3)
Java
Client
JDBC
API
JDBC Driver
Server
Native Driver
Database
JDBC Driver
This driver is Server based. So, the Vendor DB lib. Is not required for clients.
Uses DB independent Protocol to communicate DB-requests to a Server component.
Translates requests into DB-specific Protocol.
Advantages- 1. fully written in java , hence portable.
2. The net protocol can be designed to make the client JDBC driver very small
and
fast to load.
3. most efficient amongst all drivers.
Disadvantages- 1. requires another server application to be installed and maintained.
acts
2. clients connect to DB servers via an intermediate server component that
as a gateway for multiple database servers.
10. Native Protocol All-Java Driver(type4)
Java
Client
JDBC
API
JDBC Driver
Database
•JDBC calls are directly converted to network protocol used by DBMS server
•It makes direct socket connections to the databases.
Advantages – 1.written in java only. So we can achieve platform independency.
2.number of translation layers are very less.
3.performance is good.
Disadvantages –
The user need a different driver for each database
12. JDBC
There are seven standard steps in querying
databases:
1. Load the JDBC driver.
2. Define the connection URL.
3. Establish the connection.
4. Create a statement object.
5. Execute a query or update.
6. Process the results.
7. Close the connection.
13. Load the JDBC driver……………….
Only one time load in jdbc driver
How does one load a "class" into the Virtual
machine?
Use the static method Class.forName()
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver")
;
Package
ClassName
14. Define the connection URL………
•
Once a Driver is loaded, a connection can be made to the
database
•
The connection is defined by URL
• The URL has the following form:
• jdbc:driver:databasename
•
• Examples:
• jdbc:odbc:MyOdbcDatabase
• jdbc:postgres:WebsiteDatabase
• jdbc:oracle:CustomerInfo
A connection is obtained in the following manner:
• Connection conn =
DriverManager.getConnection("jdbc:odbc:MyDatabase“,"Usern
15. •
•
Establish the connection…….
The Connection interface defines many methods
for managing and using a connection to the
database
Connection aConnection;
• public Statement createStatement()
• public PreparedStatement
prepareStatement(String sql)
16. Create a statement object…….
The Statement interface .
• The most commonly used method is
createStatement()
• When an SQL statement is to be issued
against the database, a Statement object
must be created through the Connection
Connection aConnection;
17. Execute a query or update……
•
The Statement interface defines two methods
for executing SQL against the database
public ResultSet executeQuery(String sql)
public int executeUpdate(String sql)
•
executeQuery returns a ResultSet
• All rows and columns which match the query are contained
within the ResultSet
• The developer navigates through the ResultSet and uses the
data as required.
•
executeUpdate returns the number of rows
changed by the update statement
• This is used for insert statements, update statements and
delete statements