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Java连接数据库步骤

Jun 07, 2016 pm 04:48 PM
database

Java连接数据库的步骤 1. 打开连接 2. 创建语句集:普通的语句集,预定义语句集 Statement stat = conn.createStatement(); Prep

Java连接数据库的步骤

1. 打开连接
 
2. 创建语句集:普通的语句集,预定义语句集
 
Statement stat = conn.createStatement();

PreparedStatement priceUpdateStmt =

conn.prepareStatement("带问号的SQL语句");
 
priceUpdateStmt.setString(1, in.nextLine());

3. 执行语句
 
当DELETE,UPDATE,INSERT的时候使用executeUpdate()
 
executeUpdate返回一个整形数:表示删,更新,插入时受到影响的行数
 
当SELECT的时候executeQuery()
 
只有executeQuery()方法后,,才会产生ResultSet
 
ResultSet代表Select之后返回的若干行的内容
 
ResultSet调用next方法,则表示返回的一行
 
while (rs.next())
 
        {
 
            result.append(rs.getString(1));
 
            result.append(", ");
 
            result.append(rs.getString(2));
 
            result.append("\n");
 
        }

NAME
 AGE 
 
AAA
 33 
 
BBB
 55  rs

4. 关闭语句集
 
5. 关闭结果集
 
6. 关闭连接

元数据
 
ResultSet result = stat.getResultSet();
 
ResultSetMetaData metaData = result.getMetaData();
 
int columnCount = metaData.getColumnCount();
 
System.out.print(metaData.getColumnLabel(1));

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