Question

I am using following prepared statement :

 Class.forName("com.mysql.jdbc.Driver");
     con=DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql","root","root");
            String query="select ename from ? ";
            st=con.prepareStatement(query);
            st.setString(1,"emp");

Here i want to provide table name from UI,on above code i have hardcoded tablename value.when i try to execute this code i got the following excepion.

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''emp' where intensive='1000'' at line 1
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
        at com.mysql.jdbc.Util.getInstance(Util.java:381)
        at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1030)
        at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3515)
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3447)
        at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1951)
        at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2101)
        at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2554)
        at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1761)
        at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1912)
        at xmlbulkinsertoperation.getConnection.<init>(getConnection.java:42)
        at xmlbulkinsertoperation.getConnection.main(getConnection.java:70)
Mar 26, 2012 12:04:30 PM xmlbulkinsertoperation.getConnection <init>

i’m not able to solve this problem,please help me?

Thanks

Answer 1

You cannot have a prepared statement with a table name as one of the parameters. Entities (table names/db names/function names so on) cannot be parameterized in prepared statements.

You’ll have to either hard code the table name or concatenate it into the query.