mysql和jsp的String,datetime问题

[tlight]

我从用户输入的输入得到t1和t2;例如
String t1="2004-02-28 19:00:00";
String t2="2004-02-28 20:00:00";

String sql="SELECT * FROM mytable";
sql=sql+" WHERE timestamp BETWEEN "+t1+" AND "+t2;
字段timestamp是mysql的datetime类型.
我用上面的sql语句总是错.
我要查询在t1与t2之间的数据,该怎么写sql??

[互通互联]

sql=sql+" WHERE timestamp BETWEEN '"+t1+"' AND '"+t2+"'";