JDBC Driver Models

Java is a technology, which connected to database through network and forms Java Database Connection. JDBC supports two Driver models, they are

• Two tier model
• Three tier model

Two tier model

Two-tier model is a Java applet applications interact directly with the database. This type of model is referred to as client sever configuration where user is the client and machine that has the database is called as the server.

Three tier model

In this model middle tier is introduced, which is used for various purpose, there are some of the function are used in middle tier, they are

• Collection of SQL statements from the client and handing it over to the database
• Receiving results from the database to the client
• Maintaining control over accessing and updating of the data

SQL Conformance

Structured query language is the standard language used to access relational databases. Unfortunately there are no standards set at present for it. JDBC defines a set of generic SQL type identifiers in the class Java.SQL.Types

Ways of dealing with SQL conformance

JDBC deals with some of the performing SQL conformance, they are

• JDBC API allows any query string to be passed through to an underlying DBMS driver. But there are possibilities of getting an error on some DBMS.
• Provision of ODBC style escape clauses.
• Provision of descriptive information about the DBMS using an interface, Database Meta data.

Different Types of Driver Managers

JDBC contains three components: application, driver manager and driver. The user application invokes JDBC methods to send SQL statements to the database and retrieves result. JDBC driver manager is used to connect java application to the correct JDBC driver. There are four types of JDBC driver. They are

• The JDBC-ODBC Bridge plus ODBC driver
• Native-API partly-Java driver
• JDBC-Net pure Java driver
• Native-Protocol pure Java driver