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POWhy ‘No database selected’ SQLException?
 

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    <p>why this program is not executing when it goes in to the do while loop second time and why it is giving the exception "Exception java.sql.SQLException: [MySQL][ODBC 5.1 Driver][mysqld-5.0.51a-community-nt]No database selected"</p> <pre><code>//import java.io.InputStream; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.Scanner; import java.util.Vector; public class DataBase { public void LoadDriver() { // Load the JDBC-ODBC bridge driver try { Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); } catch (ClassNotFoundException ee) { ee.printStackTrace(); } } // 2.open a data source name by means of the jdbcodbcdriver. static void connect() throws SQLException { // Connect to the database Connection con = DriverManager.getConnection("jdbc:odbc:MySQL", "root", "admin"); Statement stmt = con.createStatement(); // Shut off autocommit con.setAutoCommit(false); System.out.println("1.Insert 2.Delete 3.Update 4.Select"); Scanner s = new Scanner(System.in); int x; x = s.nextInt(); String query; // SQL select string ResultSet rs; // SQL query results boolean more; // "more rows found" switch String v1, v2; // Temporary storage results Vector&lt;Object&gt; results = new Vector&lt;Object&gt;(10); if (x == 1) { try { stmt.executeUpdate("INSERT INTO employee( emp_id,emp_name ) VALUES ( '122','shiva' ) "); } catch(Exception e){System.out.println("Exception " +e);e.printStackTrace();} } if (x == 2) { try { stmt.executeUpdate("DELETE from employee where emp_id='102' "); }catch(Exception e){System.out.println("Exception "+e);e.printStackTrace();} } if (x == 3) { try { stmt .executeUpdate("UPDATE employee SET emp_name = 'madavan' where emp_id='20'; "); } catch(Exception e){System.out.println("Exception "+e);e.printStackTrace();} } query = "SELECT * FROM employee "; try { rs = stmt.executeQuery(query); // Check to see if any rows were read more = rs.next(); if (!more) { System.out.println("No rows found."); return; } // Loop through the rows retrieved from the query while (more) { v1 = "ID: " + rs.getInt("emp_id"); v2 = "Name: " + rs.getString("emp_name"); System.out.println(v1); System.out.println(v2); System.out.println(""); results.addElement(v1 + "\n" + v2 + "\n"); more = rs.next(); } rs.close(); } catch (SQLException e) { System.out.println("" + results.size() + "results where found."); } finally{stmt.close();} } public static void main(String[] args) throws SQLException { String str = "y"; do { DataBase s = new DataBase(); s.LoadDriver(); DataBase.connect(); Scanner sc = new Scanner(System.in); System.out.println("DO u Want to PROCEED TO QUERY : "); str = sc.next(); } while (str !="n"); } } </code></pre>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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