Question

In mysql command line, when i give the command:
select count(*) tables from users;
it works correctly. It gives me the size of the table.

But, i want to take the result in Java file.Thus i write in Java file the below code.But it doesn’t work

public int f()
{
   ResultSet rs;
   int i;
   String query = "select count(*) tables from users";
   Statement st = this.con.createStatement();     //error
   rs = st.executeQuery(query);                   //error
   if(rs.next())                       //error
   {                   //error
    i = rs.getInt(1);                     //error
   }
  return i;    //error
}

How can i get the size of table in my Java file?

Answer 1

you never checked if the resultSet has data using its next() method.

From ResultSet API:

The next method moves the cursor to the next row

public int f() throws SQLException {
//rest of your code
rs = st.executeQuery(query);
if(rs.next()){
i = rs.getInt(1);  
}
//rest of your code
}

also ResultSet has getInt() method not GetInt(), java is case sensitive.

EDIT: you have to handle or declare SQLException(checked exception) in your code. Connection.createStatement() would throw SQLException.