I'm newbie with mysql and this is my issue. I have a table in database called Room with one of its attribute as Floor. In the Floor column, there are 3 different names ( Walters, Gates, Pension).
I'm trying to fetch figures from table based on the selected floor and this is my query.
String query = "Select * from Rooms where Floor =" + Floor.getSelectedItem().toString();
This seems like the right query but i get an error thrown saying Unknown Column 'Walters' in where clause.
What am i not doing right?
Your query is not correct, because String should be between to quotes ""
:
String query =
"Select * from Rooms where Floor = '" + Floor.getSelectedItem().toString() + "'";
//----------------------------------^------------------------------------------^
But this not secure, instead read about Prepared Statement to avoid SQL Injection and syntax error :
String query = "Select * from Rooms where Floor = ?";
PreparedStatement pstmt = con.prepareStatement(query);
pstmt.setString(1, Floor.getSelectedItem().toString());
pstmt.executeQuery();//then execute the statement
strings in a query should be in single quotes, your query should be:
Select * from Rooms where Floor = 'Walter';
so your code should be:
String query = "Select * from Rooms where Floor = '" + Floor.getSelectedItem().toString() + "'";
It is better to use PreparedStatements to avoid confusion
用这个,
String query = "Select * from Rooms where Floor ='" + Floor.getSelectedItem().toString();+"'"
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