Oracle database connection configuration and application
Oracle database connection mode configuration and application
As a well-known relational database management system in the industry, Oracle database has powerful data management and data processing capabilities, and has a wide range of Used in enterprise-level systems. In actual development and application, it is crucial to correctly configure the database connection method and apply it rationally. This article will introduce the configuration method of Oracle database connection and specific code examples to help readers better configure and apply Oracle database connection.
- JDBC connection method
JDBC is the standard for Java database connection. Through JDBC, the connection between Java program and Oracle database can be realized. The following is a simple Java code example that demonstrates how to connect to an Oracle database through JDBC and perform simple query operations:
import java.sql.*; public class OracleJDBCExample { public static void main(String[] args) { String url = "jdbc:oracle:thin:@localhost:1521:ORCL"; String user = "username"; String password = "password"; try { Class.forName("oracle.jdbc.driver.OracleDriver"); Connection conn = DriverManager.getConnection(url, user, password); Statement stmt = conn.createStatement(); ResultSet rs = stmt.executeQuery("SELECT * FROM emp"); while (rs.next()) { System.out.println(rs.getInt(1) + " " + rs.getString(2)); } rs.close(); stmt.close(); conn.close(); } catch (Exception e) { e.printStackTrace(); } } }
In the above code, you need to replace url
, user
and password
are the actual database connection information, where jdbc:oracle:thin:@localhost:1521:ORCL
is the URL to connect to the Oracle database, emp
is the table name in the database.
- Use data source connection pool
The data source connection pool can effectively manage database connections and improve connection reusability and performance. The following is a configuration example using the Apache Commons DBCP connection pool:
import org.apache.commons.dbcp2.BasicDataSource; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; public class OracleDBCPExample { public static void main(String[] args) { BasicDataSource ds = new BasicDataSource(); ds.setDriverClassName("oracle.jdbc.driver.OracleDriver"); ds.setUrl("jdbc:oracle:thin:@localhost:1521:ORCL"); ds.setUsername("username"); ds.setPassword("password"); try (Connection conn = ds.getConnection(); PreparedStatement ps = conn.prepareStatement("SELECT * FROM emp"); ResultSet rs = ps.executeQuery()) { while (rs.next()) { System.out.println(rs.getInt(1) + " " + rs.getString(2)); } } catch (Exception e) { e.printStackTrace(); } } }
In the above code, a data source connection pool is created using Apache Commons DBCP, and the database connection is obtained through the connection pool for query operations.
- Using the JdbcTemplate of the Spring framework
The Spring framework provides the JdbcTemplate tool class to simplify database operations. The following is an example of using Spring's JdbcTemplate to connect to an Oracle database:
import org.springframework.jdbc.core.JdbcTemplate; import javax.sql.DataSource; public class OracleJdbcTemplateExample { private JdbcTemplate jdbcTemplate; public OracleJdbcTemplateExample(DataSource dataSource) { this.jdbcTemplate = new JdbcTemplate(dataSource); } public void queryData() { String sql = "SELECT * FROM emp"; jdbcTemplate.query(sql, (rs, rowNum) -> rs.getInt(1) + " " + rs.getString(2)) .forEach(System.out::println); } }
In the above code, the data source is injected through Spring and JdbcTemplate is used to perform query operations.
Summary: This article introduces the configuration and application of Oracle database connection methods, including the use of JDBC, data source connection pool and JdbcTemplate of the Spring framework. Readers can choose the appropriate connection method according to specific needs, and configure and apply it with code examples to improve the efficiency and reliability of database operations. I hope this article can help readers better understand and apply Oracle database connections.
The above is the detailed content of Oracle database connection configuration and application. For more information, please follow other related articles on the PHP Chinese website!

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