String sql = "select * from user where name='"+ uname +"' and passwd='"+ passwd +"'"; 呵呵,这样对了
String sql = "select * from user where name='"+ uname +"'" + and passwd="'"+ passwd +"'"; 改成 String sql = "select * from user where name='"+ uname +"' and passwd= '"+ passwd +"' ";
String sql = "select * from user where name='"+ uname +"'" + and passwd="'"+ passwd +"'"; 改成 String sql = "select * from user where name='"+ uname +"' and passwd= '"+ passwd +"' "; 变量的写法 假设a 为变量 则再sql语句中,应该是 1)当按条件查询时候 如 string sql="select * from table1 where username='aaa' ";2) 如果使用变量 a ,代替'aaa' 则 string sql="select * from table1 where username='"+a+"' ";总之,sql语句正常写将出现变量的地方写成 '"+变量+"' ,其他地方保持不变,就可以了
呵呵,这样对了
改成
String sql = "select * from user where name='"+ uname +"' and passwd= '"+ passwd +"' ";
改成
String sql = "select * from user where name='"+ uname +"' and passwd= '"+ passwd +"' ";
变量的写法
假设a 为变量
则再sql语句中,应该是
1)当按条件查询时候 如
string sql="select * from table1 where username='aaa' ";2) 如果使用变量 a ,代替'aaa' 则
string sql="select * from table1 where username='"+a+"' ";总之,sql语句正常写将出现变量的地方写成
'"+变量+"' ,其他地方保持不变,就可以了