Com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException:Unknown column

Com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException:Unknown column ... The great possibility of this exception is that the database is no problem!    The key reason is: You pass the argument is a string type, we manipulate the database when the string type parameter must be used to "the parameter can be passed and received!" For example Rs=stmt.executequery ("select * from userinfo where UserID = '" +id+ ""); ID is a string type, in the database operation, do not miss the two sides of the single quotation marks, remember!!! Often wrong point!!!

Com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException:Unknown column