Java如何获取列的精度和小数位值？
例如，您在数据库表中有一个数字或双精度类型的列，并且您想要获得该列的精度和小数位数。这是给你的例子。
package org.nhooo.example.jdbc;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
public class ScaleAndPrecisionExample {
private static final String URL = "jdbc:mysql://localhost/nhooo";
private static final String USERNAME = "root";
private static final String PASSWORD = "";
public static void main(String[] args) {
try (Connection connection =
DriverManager.getConnection(URL, USERNAME, PASSWORD)) {
Statement statement = connection.createStatement();
String query = "SELECT id, quantity, price FROM order_details";
ResultSet resultSet = statement.executeQuery(query);
ResultSetMetaData metadata = resultSet.getMetaData();
int precision = metadata.getPrecision(3);
int scale = metadata.getScale(3);
System.out.println("Precision: " + precision);
System.out.println("Scale : " + scale);
} catch (SQLException e) {
e.printStackTrace();
}
}
}结果：
Precision: 10 Scale : 2
Maven依赖
<!-- https://search.maven.org/remotecontent?filepath=mysql/mysql-connector-java/8.0.17/mysql-connector-java-8.0.17.jar -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.17</version>
</dependency>