Question

Oracle模糊查询怎么给？传值，下面的代码java.sql.SQLException: 无效的列索引，谢谢

//模糊查询
public void selbylike(String x){
Connection conn = null;
conn= cf.getconn();
PreparedStatement prep = null;
ResultSet rs = null;
String sql = "select * from emp where ename like '%'+?+'%'";
try {
prep = conn.prepareStatement(sql);
prep.setString(0, x);
rs = prep.executeQuery();
while(rs.next()){
System.out.println(rs.getInt("empno")+" "+rs.getString("ename") + " "+rs.getString(3)+ " "+rs.getString(4)+ " "+rs.getString(5)+ " "+rs.getString(6)+ " "+rs.getString(7)+ " "+rs.getString(8));
}
} catch (SQLException e) {
e.printStackTrace();
}

}

Answer 1

不是这 String sql = "select * from emp where ename like '%'+?+'%'";
String sql = "select * from emp where ename like '%?%'";
就是这System.out.println(rs.getInt("empno")+" "+rs.getString("ename") + " "+rs.getString(3)+ " "+rs.getString(4)+ " "+rs.getString(5)+ " "+rs.getString(6)+ " "+rs.getString(7)+ " "+rs.getString(8));

错了，你看看emp是不是有empno和ename的属性，再看看第3，4，5，6，7，8个属性是否有值，并且是不是String类型的

追问

这个没有问题。

追答

prep.setParameter(0, x);

Answer 2

oracle字符串相加是||不是+

追问

改成||也没用，一样的错误

追答

另外还有1个错误，就是参数的下标
sql = "select * from emp where ename like '%'||?||'%'";
prep.setString(1, x);
我这里测试一切正常

Answer 3

String sql = "select * from emp where ename like '%"+?+"%'";
不是单引号多了，而是双引号少了，你原来的相当于是直接like %'?'% 这么一个字符串了，而不是like '%?%'

Answer 4

select * from emp where ename like '%+?+%'
多了两个单引号

追问

没用，一样的错误