java用odbc连接数据库后,select * from Table时怎么锁住表? 或许可以先update a=aselect *commit 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 我是想select时锁住表,取出纪录后在解锁。有什么方法? 下面有个例子:String query = null;ResultSet r = null;String tablename = XXX;//table's name;try { Statement s = conn.createStatement(); query = "lock tables " + tablename + " write"; r = s.executeQuery(query); query = "select max(id) from " + tablename; r = s.executeQuery(query); if (r.next()){ ...... } query = "unlock tables"; r = s.executeQuery(query); r.close(); s.close();}catch (SQLException e){ System.out.println ("SQL error:" + e); return "e";} 在你的 更改sql 语句后加for update 就可以了 你只是select数据,有必要加锁吗?? sql 语句后加for updat nowait 同时select表Table1,Table2,需要把Table1锁住,然后再解锁。Statement rs = conn.createStatement();Statement rs1 = conn.createStatement();rs.executeQuery("select * from Table1,Table2");//Table1需锁住,Table2不锁while(rs.next()) { rs1.executeQuery("select * from Table2 where ..."); ...}rs.close();update Table1...;解锁Table1...打楷就这样,该如何锁住表Table1? Yes. set TransactionIsolution.@see javadoc api : java.sql.Connection java.lang.NullPointerException 数组分割问题。。。 Java的多语言支持问题 java.lang.integer错误 北京到那里学java好 求阶层代码 定义final int i = new int[2];之后树组维数无法改变,但内容可变,如何使内容也不可变 怎样添加 JScrollPane的事件 谢谢 jbuild下的包问题? 在线等待,怎样用html调用我自己的类(从JApplet派生的)、急!急!急!急!急! 在Java中如何将UNICODE码转换成GB码 请问如何运用reflection机制,通过non-default构造函数产生对象?
String query = null;
ResultSet r = null;
String tablename = XXX;//table's name;
try {
Statement s = conn.createStatement();
query = "lock tables " + tablename + " write";
r = s.executeQuery(query);
query = "select max(id) from " + tablename;
r = s.executeQuery(query);
if (r.next()){
......
}
query = "unlock tables";
r = s.executeQuery(query);
r.close();
s.close();
}catch (SQLException e)
{
System.out.println ("SQL error:" + e);
return "e";
}
Statement rs1 = conn.createStatement();
rs.executeQuery("select * from Table1,Table2");//Table1需锁住,Table2不锁
while(rs.next())
{
rs1.executeQuery("select * from Table2 where ...");
...
}
rs.close();
update Table1...;
解锁Table1...打楷就这样,该如何锁住表Table1?
@see javadoc api : java.sql.Connection