Java学习笔记――JDBC之与数据库MySQL的连接以及增删改查等操作 (三)

//执行一条查询类SQL，返回单条记录集
public void QurtyByUnique(String sql) {
getConnection();
try {
statement = connection.createStatement();
rSet = statement.executeQuery(sql);
System.out.println("id\t" + "realName\t"+"school\t");
if (rSet.next()) {
System.out.println(rSet.getInt("id") + "\t" + rSet.getString("realName") + "\t" + rSet.getString("school") + "\t");
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally{
try {
if (statement != null) {
statement.close();
statement = null;
}
if (rSet != null) {
rSet.close();
rSet = null;
}
} catch (SQLException e2) {
// TODO: handle exception
}
}
}应用举例：
[java]
jDao.QurtyByUnique("SELECT * FROM t_user WHERE sex='女';");
System.out.println("-----------------------------");
jDao.QurtyByUnique("SELECT * FROM t_user;");
System.out.println("-----------------------------");

jDao.QurtyByUnique("SELECT * FROM t_user WHERE sex='女';");
System.out.println("-----------------------------");
jDao.QurtyByUnique("SELECT * FROM t_user;");
System.out.println("-----------------------------");

输出表单所有数据
[java]
public void QurtyTest(String sql) {
getConnection();
try {
statement = connection.createStatement();
rSet = statement.executeQuery(sql);
while (rSet.next()) {
System.out.print(rSet.getRow()+ "----" );
for (int i = 1; i < 14; i++) {
System.out.print(rSet.getString(i) +"\t");
}
System.out.println();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally{
try {
if (statement != null) {
statement.close();
statement = null;
}
if (rSet != null) {
rSet.close();
rSet = null;
}
} catch (SQLException e2) {
// TODO: handle exception
}
}
}

public void QurtyTest(String sql) {
getConnection();
try {
statement = connection.createStatement();
rSet = statement.executeQuery(sql);
while (rSet.next()) {
System.out.print(rSet.getRow()+ "----" );
for (int i = 1; i < 14; i++) {
System.out.print(rSet.getString(i) +"\t");
}
System.out.println();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally{
try {
if (statement != null) {
statement.close();
statement = null;
}
if (rSet != null) {
rSet.close();
rSet = null;
}
} catch (SQLException e2) {
// TODO: handle exception
}
}
} 应用举例
[java]
jDao.QurtyTest("SELECT * FROM t_user;");