Database Lesson 4

One thing we haven't covered so far in our telephony application is the ability of users to add themselves to the database if no entry already exists.


    • Sample Files:
      • Samples\database_4.py

      Updating the code

      We now have a general get_age() function which does the DTMF detection for an age, and strips out the end key before returning the string.

      Updating a PIN code has been moved to a separate subroutine, update_pin_code.

      Insertion into the DB

      For inserting into the database, we first check if the user has a PIN code in the database. If there is no entry found, the user is asked if they would like to add an entry using the keypad. Once the age has been entered, the create_new_entry subroutine is called.

      This creates a query string with the insert into method, with the PIN code and age as arguments.

    • """
      This application is part of the online database tutorial.
      """
      
      # mysql is available at https://dev.mysql.com/downloads/connector/python
      try:
          import mysql.connector
      except:
          raise Exception("database_4 needs mysql which is available at https://dev.mysql.com/downloads/connector/python")
      
      from prosody.uas import Hangup, Error
      
      __uas_version__ = "0.0.1"
      __uas_identify__ = "application"
      
      def get_age(channel):
          channel.FilePlayer.say("Please enter an age entry, followed by the hash key")
          dtmf = channel.DTMFDetector.get_digits(end='#', clear=True,
                                                 seconds_predigits_timeout=10, seconds_interdigit_timeout=30)
          cause = channel.DTMFDetector.cause()
      
          if cause == channel.DTMFDetector.Cause.END:
              # Strip off the last end character
              return dtmf[:-1]
          else:
              return None
      
      def update_pin_code(channel, pin, cursor):
          age = get_age(channel)
          if age:
              cursor.execute("""update users set age={0} where pin={1};""".format(age,pin));
      
      def create_new_entry(channel, pin, cursor, my_log):
          age = get_age(channel)
          if age:
              cursor.execute("""insert into users values({0},{1});""".format(pin,age));
      
      def main(channel, application_instance_id, file_man, my_log, application_parameters):
          return_code = 0
      
          try:
      
              channel.ring(2)
              channel.answer()
      
              channel.FilePlayer.say("Welcome to the database example. Please enter a four digit PIN code")
      
              pin = channel.DTMFDetector.get_digits(count=4, seconds_predigits_timeout=30)
      
              if channel.DTMFDetector.cause() != channel.DTMFDetector.Cause.COUNT:
                  channel.FilePlayer.say("No valid input detected")
              else:
                  conn = mysql.connector.connect(host="localhost", user="root", passwd="aculab", db="test")
                  cursor = conn.cursor()
                  cursor.execute("""select * from users where pin={0};""".format(pin))
                  data = cursor.fetchall()
      
                  if len(data) == 1:
                      # One found, that's normal!
                      channel.FilePlayer.say("You have been found in the database. Your age entry value is {0}.".format(data[0][1]))
      
                      channel.FilePlayer.say("Press 1 to alter this entry")
                      digit = channel.DTMFDetector.get_digits(count=1, seconds_predigits_timeout=30)
                      if channel.DTMFDetector.cause() == channel.DTMFDetector.Cause.COUNT:
                          if digit == '1':
                              update_pin_code(channel, pin, cursor)
                              conn.commit()
                  else:
                      channel.FilePlayer.say("No entry in database. Press 1 to create a new entry with this pin code")
                      digit = channel.DTMFDetector.get_digits(count=1, seconds_predigits_timeout=30)
                      if channel.DTMFDetector.cause() == channel.DTMFDetector.Cause.COUNT:
                          if digit == '1':
                              create_new_entry(channel, pin, cursor, my_log)
                              conn.commit()
      
              channel.FilePlayer.say("Good bye")
      
          except Hangup as exc:
              my_log.info("Hangup exception reports: {0}".format(exc))
               # in this app a hangup is not an error, return a positive value
              return_code = 100
      
          except Error as exc:
              # for error conditions return a negative value
              my_log.error("Error exception reports: {0}".format(exc))
              return_code = -101
      
          except Exception as exc:
              # an unexpected exception, return a negative value
              my_log.exception("Unexpected exception reports: {0}".format(exc))
              return_code = -102
      
          finally:
              if channel.state() != channel.State.IDLE:
                  channel.hang_up()
      
          return return_code
                                  
    • Sample Files:
      • Samples\UASApplications\Database4\src\main\java\com\aculab\uas\app\Database4.java

      Updating the Code

      We now have a general getAge() method that performs the DTMF detection to obtain a DTMF string from the caller and strips out the end key before returning the new age value.

      Updating a PIN code has been moved to a separate method updatePINCode.

      Insertion into the Database

      To create a new entry, the new method createNewEntry has been added. This works primarily in the same way that updatePINCode() does, apart from the SQL query. It uses an insert command here, taking the PIN code and entered age as parameters.

    • package com.aculab.uas.app;
      
      // An inbound application that opens a local database, answers the call and
      // prompts the caller to enter a four digit pin code. It then queries the database
      // for the age associated with the entered pin code and says it to the caller.
      // The caller can then choose to enter a new age into the database.
      // If the pin code isn't in the database the caller has the option to add
      // the new pin code and enter an age to be associated with it.
      import java.sql.Connection;
      import java.sql.DriverManager;
      import java.sql.PreparedStatement;
      import java.sql.ResultSet;
      
      import com.aculab.amsapi.*;
      import com.aculab.uasapi.*;
      
      // The application class.
      // This must extend either UASInboundApplication or UASOutboundApplication and
      // override the run method.
      // It must be packaged in a jar file of the same name together with a manifest file.
      public class Database4 extends UASInboundApplication
      {
      	// Success Codes:
      	final int Success = 0;
          // ... any positive integer
      
      	// Fail Codes:
      	// -1 to -99 reserved
      	final int ExceptionThrown = -100;
      
      
          // This is the entry point for the application
      	@Override
      	public int run(UASCallChannel channel,
                         String applicationParameters)
      		throws Exception
          {
      		this.getTrace().traceInfo("Start - appParms [%s]", applicationParameters);
      		int returnCode = Success;
      
      		Connection myConnection = null;
      
              try
              {
                  // Create Database Connection Object
              	String databaseName = "test";
              	String con = String.format("jdbc:mysql://localhost/%s?user=%s&password=%s",
              			databaseName, "user", "password");
              	Class.forName("com.mysql.jdbc.Driver");
              	myConnection = DriverManager.getConnection(con);
      
                  PreparedStatement myCommand = myConnection.prepareStatement("use " + databaseName);
          	    myCommand.execute();
      
                  // Answer the call
                  CallState state = channel.answer();
                  if (state == CallState.Answered)
                  {
                      this.getTrace().traceInfo("Call answered");
      
                      // Prompt for a pin code, allowing barge in
                      channel.getFilePlayer().say("Welcome to the database example. " +
                              "Please enter a four digit PIN code.", true);
      
                      // Allow the user to enter a four digit PIN code
                      String digits = channel.getDtmfDetector().getDigits(4, 30);
                      DtmfDetectorCause cause = channel.getDtmfDetector().getCause();
                      if (cause == DtmfDetectorCause.Count)
                      {
                          // Create the SQL search query
                          PreparedStatement command = myConnection.prepareStatement(
                          		String.format("select age from users where pin=%s", digits));
                          ResultSet results = command.executeQuery();
      
                          // Read the results
                          if (results.first())
                          {
                          	do
      	                    {
      	                        String age = results.getString("age");
      	                        this.getTrace().traceInfo("Data %s", age);
      
      	                        // Say the age corresponding to the supplied pin code
      	                        channel.getFilePlayer().say("You have been found in the database. Your age entry value is " + age);
      
      	                        // Also send the age via dtmf digits
      	                        channel.getDtmfPlayer().play(age);
      	                    } while (results.next());
      
                          	// Close the results object.
                              results.close();
      
                              channel.getFilePlayer().say("Press 1 to alter this entry", true);
      
                              String menu = channel.getDtmfDetector().getDigits(1, 30);
                              if (channel.getDtmfDetector().getCause() == DtmfDetectorCause.Count)
                              {
                                  if (menu.charAt(0) == '1')
                                  {
                                      returnCode = updatePINCode(channel, digits, myConnection);
                                  }
                              }
                          }
                          else
                          {
      	                    // Close the reader object
      	                    results.close();
      
      	                    channel.getFilePlayer().say("No entry in database. Press 1 to create a " +
      	                        "new entry with this pin code", true);
      
      	                    String menu = channel.getDtmfDetector().getDigits(1, 30);
      	                    if (channel.getDtmfDetector().getCause() == DtmfDetectorCause.Count)
      	                    {
      	                        if (menu.charAt(0) == '1')
      	                        {
      	                            returnCode = createNewEntry(channel, digits, myConnection);
      	                        }
      	                    }
                          }
                      }
      
                      channel.getFilePlayer().say("Goodbye.");
                  }
                  else
                  {
                      channel.getFilePlayer().say("No valid input detected");
                  }
              }
              catch (Exception except)
              {
                  this.getTrace().traceError("Exception thrown %s", except.getMessage());
                  returnCode = ExceptionThrown;
              }
              finally
              {
                  // Close the database connection
                  if (myConnection != null)
                  {
                      myConnection.close();
                  }
      
                  // Hang up the call
                  channel.hangUp();
              }
      
      	    this.getTrace().traceInfo("Completed with return code %d", returnCode);
      	    return returnCode;
          }
      
          private String getAge(UASCallChannel channel)
          		throws InterruptedException, IllegalArgumentException, ObjectDisposedException, IllegalStateException
          {
              channel.getFilePlayer().say("Please enter an age entry, " +
                     "followed by the hash key", true);
      
              // Allow the user to enter an age value
              String age = channel.getDtmfDetector().getDigits(0, new char[] { '#', '*' }, false, 10, 30);
              DtmfDetectorCause cause = channel.getDtmfDetector().getCause();
              if (cause == DtmfDetectorCause.End)
              {
                  return age.substring(0, age.length() - 1);
              }
              return null;
          }
      
          private int updatePINCode(UASCallChannel channel, String PIN, Connection db)
          		throws InterruptedException, IllegalArgumentException, ObjectDisposedException, IllegalStateException
          {
              int returnCode = Success;
      
              String age = getAge(channel);
              if (age != null)
              {
                  String command = String.format("update users set age=%s where pin=%s;", age, PIN);
      
                  try
                  {
                      PreparedStatement myCommand = db.prepareStatement(command);
              	    myCommand.execute();
      
                      channel.getFilePlayer().say("The database has been updated.");
                  }
                  catch (Exception except)
                  {
                      this.getTrace().traceError("Exception thrown %s", except.getMessage());
                      returnCode = ExceptionThrown;
                  }
              }
      
              return returnCode;
          }
      
          private int createNewEntry (UASCallChannel channel, String PIN, Connection db)
          		throws InterruptedException, IllegalArgumentException, ObjectDisposedException, IllegalStateException
          {
              int returnCode = Success;
      
              String age = getAge(channel);
              if (age != null)
              {
                  String command = String.format("insert into users values (%s,%s);", PIN, age);
      
                  try
                  {
                      PreparedStatement myCommand = db.prepareStatement(command);
              	    myCommand.execute();
      
                      channel.getFilePlayer().say("The database has been updated.");
                  }
                  catch (Exception except)
                  {
                      this.getTrace().traceError("Exception thrown %s", except.getMessage());
                      returnCode = ExceptionThrown;
                  }
              }
      
              return returnCode;
          }
      }
                                  
    • Sample Files:
      • Samples\C#\Database4\Database4.cs

      Updating the Code

      We now have a general GetAge() method that performs the DTMF detection to obtain a DTMF string from the caller and strips out the end key before returning the new age value.

      Updating a PIN code has been moved to a separate method UpdatePINCode.

      Insertion into the Database

      To create a new entry, the new method CreateNewEntry has been added. This works primarily in the same way that UpdatePINCode() does, apart from the SQL query. It uses an insert command here, taking the PIN code and entered age as parameters.

    • using System;
      using System.Threading;
      using AMSClassLibrary;
      using UASAppAPI;
      using System.Collections.Generic;
      using System.Text;
      using System.Data.SqlClient;
      
      // An inbound application that opens a local database, answers the call and
      // prompts the caller to enter a four digit pin code. It then queries the database
      // for the age associated with the entered pin code and says it to the caller.
      // The caller can then choose to enter a new age into the database.
      // If the pin code isn't in the database the caller has the option to add
      // the new pin code and enter an age to be associated with it.
      namespace Database4
      {
          // The application class.
          // This must have the same name as the assembly and must inherit from either
          // UASInboundApplication or UASOutboundApplication.
          // It must override the Run method.
          public class Database4 : UASInboundApplication
          {
              // Possible return codes
              enum ReturnCode
              {
                  // Success Codes:
                  Success = 0,
                  // ... any positive integer
      
                  // Fail Codes:
                  // -1 to -99 reserved
                  ExceptionThrown = -100
              }
      
              private string GetAge(UASCallChannel channel)
              {
                  channel.FilePlayer.Say("Please enter an age entry, " +
                         "followed by the hash key", true);
      
                  // Allow the user to enter an age value
                  string age;
                  DtmfDetectorCause cause = channel.DtmfDetector.GetDigits(
                                          0, new char[] { '#', '*' }, out age, false, 10, 30);
      
                  if (cause == DtmfDetectorCause.End)
                  {
                      return age.Remove(age.Length - 1, 1);
                  }
                  return null;
              }
      
              private ReturnCode UpdatePINCode(UASCallChannel channel, string PIN, SqlConnection db)
              {
                  ReturnCode reply = ReturnCode.Success;
      
                  string age = GetAge(channel);
                  if (age != null)
                  {
                      string command = "update users set age=" + age +
                          " where pin=" + PIN + ";";
      
                      try
                      {
                          SqlCommand myCommand = new SqlCommand(command, db);
                          myCommand.ExecuteNonQuery();
      
                          channel.FilePlayer.Say("The database has been updated.");
                      }
                      catch (Exception except)
                      {
                          this.Trace.TraceError("Exception thrown {0}", except.Message);
                          reply = ReturnCode.ExceptionThrown;
                      }
                  }
      
                  return reply;
              }
      
              private ReturnCode CreateNewEntry (UASCallChannel channel, string PIN, SqlConnection db)
              {
                  ReturnCode reply = ReturnCode.Success;
      
                  string age = GetAge(channel);
                  if (age != null)
                  {
                      string command = "insert into users values (" + PIN + "," + age + ")";
      
                      try
                      {
                          SqlCommand myCommand = new SqlCommand(command, db);
                          myCommand.ExecuteNonQuery();
      
                          channel.FilePlayer.Say("The database has been updated.");
                      }
                      catch (Exception except)
                      {
                          this.Trace.TraceError("Exception thrown {0}", except.Message);
                          reply = ReturnCode.ExceptionThrown;
                      }
                  }
      
                  return reply;
              }
      
      
              // This is the entry point for the application
              public override int Run(UASCallChannel channel,
                                      string applicationParameters)
              {
                  this.Trace.TraceInfo("Started");
                  ReturnCode reply = ReturnCode.Success;
                  SqlConnection myConnection = null;
      
                  try
                  {
                      // Create Database Connection Object
                      myConnection = new SqlConnection("server=.\\SQLEXPRESS;" +
                                             "Trusted_Connection=yes;" +
                                             "database=test; " +
                                             "connection timeout=30");
      
                      // Make the connection
                      myConnection.Open();
      
                      // Answer the call
                      CallState state = channel.Answer();
                      if (state == CallState.Answered)
                      {
                          this.Trace.TraceInfo("Call answered");
      
                          // Prompt for a pin code, allowing barge in
                          channel.FilePlayer.Say("Welcome to the database example. " +
                                  "Please enter a four digit PIN code.", true);
      
                          // Allow the user to enter a four digit PIN code
                          string digits;
                          DtmfDetectorCause cause = channel.DtmfDetector.GetDigits(4, out digits, 30);
                          if (cause == DtmfDetectorCause.Count)
                          {
                              SqlDataReader myReader = null;
      
                              // Create the SQL search query
                              SqlCommand myCommand = new SqlCommand("select age from users where pin=" + digits,
                                                                       myConnection);
                              // Create a reader object
                              myReader = myCommand.ExecuteReader();
      
                              // Check if there are any elements returned
                              if (myReader.HasRows)
                              {
                                  // Read the row data
                                  while (myReader.Read())
                                  {
                                      string age = myReader["age"].ToString();
                                      this.Trace.TraceInfo("Data {0}", age);
      
                                      // Say the age corresponding to the supplied pin code
                                      channel.FilePlayer.Say("You have been found in the database. Your age entry value is " + age);
      
                                      // Also send the age via dtmf digits
                                      channel.DtmfPlayer.Play(age);
                                  }
      
                                  // Close the reader object.
                                  myReader.Close();
      
                                  channel.FilePlayer.Say("Press 1 to alter this entry", true);
      
                                  string menu;
                                  cause = channel.DtmfDetector.GetDigits(1, out menu, 30);
                                  if (cause == DtmfDetectorCause.Count)
                                  {
                                      if (menu[0] == '1')
                                      {
                                          reply = UpdatePINCode(channel, digits, myConnection);
                                      }
                                  }
                              }
                              else
                              {
                                  // Close the reader object
                                  myReader.Close();
      
                                  channel.FilePlayer.Say("No entry in database. Press 1 to create a " +
                                      "new entry with this pin code", true);
      
                                  string menu;
                                  cause = channel.DtmfDetector.GetDigits(1, out menu, 30);
                                  if (cause == DtmfDetectorCause.Count)
                                  {
                                      if (menu[0] == '1')
                                      {
                                          reply = CreateNewEntry(channel, digits, myConnection);
                                      }
                                  }
                              }
                          }
                          else
                              channel.FilePlayer.Say("No valid input detected");
      
                          channel.FilePlayer.Say("Goodbye.");
                      }
                  }
                  catch (Exception except)
                  {
                      this.Trace.TraceError("Exception thrown {0}", except.Message);
                      reply = ReturnCode.ExceptionThrown;
                  }
                  finally
                  {
                      // Close the database connection
                      if (myConnection != null)
                      {
                          myConnection.Close();
                      }
      
                      // Hang up the call
                      channel.HangUp();
                  }
      
                  this.Trace.TraceInfo("Completed");
                  return (int)reply;
              }
          }
      }
                                  
    • Sample Files:
      • Samples\VB\Database4\Database4.vb

      Updating the Code

      We now have a general GetAge() method that performs the DTMF detection to obtain a DTMF string from the caller and strips out the end key before returning the new age value.

      Updating a PIN code has been moved to a separate method UpdatePINCode.

      Insertion into the Database

      To create a new entry, the new method CreateNewEntry has been added. This works primarily in the same way that UpdatePINCode() does, apart from the SQL query. It uses an insert command here, taking the PIN code and entered age as parameters.

    • Imports AMSClassLibrary
      Imports UASAppAPI
      Imports System.Data.SqlClient
      
      ' An inbound application that opens a local database, answers the call and
      ' prompts the caller to enter a four digit pin code. It then queries the database
      ' for the age associated with the entered pin code and says it to the caller.
      ' The caller can then choose to enter a new age into the database.
      ' If the pin code isn't in the database the caller has the option to add
      ' the new pin code and enter an age to be associated with it.
      Namespace Database4
      
          ' The application class.
          ' This must have the same name as the assembly and must inherit from either
          ' UASInboundApplication or UASOutboundApplication.
          ' It must override the Run method.
          Public Class Database4
              Inherits UASInboundApplication
      
              ' Possible return codes
              Enum ReturnCode
                  ' Success Codes:
                  Success = 0
                  ' ... any positive integer
      
                  ' Fail Codes:
                  ' -1 to -99 reserved
                  ExceptionThrown = -100
              End Enum
      
              Private Function GetAge(ByVal channel As UASCallChannel) As String
                  channel.FilePlayer.Say("Please enter an age entry, " + _
                         "followed by the hash key", True)
      
                  ' Allow the user to enter an age value
                  Dim age As String = ""
                  Dim cause = channel.DtmfDetector.GetDigits(0, New Char() {"#", "*"}, age, False, 10, 30)
      
                  If cause = DtmfDetectorCause.End Then
                      Return age.Remove(age.Length - 1, 1)
                  End If
      
                  Return Nothing
              End Function
      
              Private Function UpdatePINCode(ByVal channel As UASCallChannel, ByVal PIN As String, ByVal db As SqlConnection) As ReturnCode
                  Dim reply = ReturnCode.Success
      
                  Dim age = GetAge(channel)
                  If Not age Is Nothing Then
                      Dim command = "update users set age=" + age + _
                          " where pin=" + PIN + ";"
      
                      Try
                          Dim myCommand = New SqlCommand(command, db)
                          myCommand.ExecuteNonQuery()
      
                          channel.FilePlayer.Say("The database has been updated.")
                      Catch except As Exception
                          Me.Trace.TraceError("Exception thrown {0}", except.Message)
                          reply = ReturnCode.ExceptionThrown
                      End Try
                  End If
      
                  Return reply
              End Function
      
              Private Function CreateNewEntry(ByVal channel As UASCallChannel, ByVal PIN As String, ByVal db As SqlConnection) As ReturnCode
                  Dim reply = ReturnCode.Success
      
                  Dim age = GetAge(channel)
                  If Not age Is Nothing Then
                      Dim command = "insert into users values (" + PIN + "," + age + ")"
      
                      Try
                          Dim myCommand = New SqlCommand(command, db)
                          myCommand.ExecuteNonQuery()
      
                          channel.FilePlayer.Say("The database has been updated.")
                      Catch except As Exception
                          Me.Trace.TraceError("Exception thrown {0}", except.Message)
                          reply = ReturnCode.ExceptionThrown
                      End Try
                  End If
      
                  Return reply
              End Function
      
              ' This is the entry point for the application
              Overrides Function Run(ByVal channel As UASCallChannel, _
                                     ByVal applicationParameters As String) _
                                     As Integer
      
                  Me.Trace.TraceInfo("Started")
                  Dim reply As ReturnCode = ReturnCode.Success
                  Dim myConnection As SqlConnection = Nothing
      
                  Try
                      ' Create Database Connection Object
                      myConnection = New SqlConnection("server=.\SQLEXPRESS;" + _
                                                       "Trusted_Connection=yes;" + _
                                                       "database=test; " + _
                                                       "connection timeout=30")
      
                      ' Make the connection
                      myConnection.Open()
      
                      ' Answer the call
                      Dim state As CallState
                      state = channel.Answer()
                      If state = CallState.Answered Then
                          Me.Trace.TraceInfo("Call answered")
      
                          ' Prompt for a pin code, allowing barge in
                          channel.FilePlayer.Say("Welcome to the database example. " + _
                                                 "Please enter a four digit PIN code.", True)
      
                          ' Allow the user to enter a four digit PIN code
                          Dim digits As String = ""
                          Dim cause = channel.DtmfDetector.GetDigits(4, digits, 30)
                          If cause = DtmfDetectorCause.Count Then
                              Dim myReader As SqlDataReader = Nothing
      
                              ' Create the SQL search query
                              Dim myCommand = New SqlCommand("select age from users where pin=" + digits, _
                                                                       myConnection)
                              ' Create a reader object
                              myReader = myCommand.ExecuteReader()
      
                              ' Check if there are any elements returned
                              If myReader.HasRows Then
                                  ' Read the row data
                                  While myReader.Read()
                                      Dim age = myReader("age").ToString()
                                      Me.Trace.TraceInfo("Data {0}", age)
      
                                      ' Say the age corresponding to the supplied pin code
                                      channel.FilePlayer.Say("You have been found in the database. " + _
                                                             "Your age entry value is " + age)
      
                                      ' Also send the age via dtmf digits
                                      channel.DtmfPlayer.Play(age)
                                  End While
      
                                  ' Close the reader object.
                                  myReader.Close()
      
                                  channel.FilePlayer.Say("Press 1 to alter this entry", True)
      
                                  Dim menu As String = ""
                                  cause = channel.DtmfDetector.GetDigits(1, menu, 30)
                                  If cause = DtmfDetectorCause.Count Then
                                      If (menu(0) = "1") Then
                                          reply = UpdatePINCode(channel, digits, myConnection)
                                      End If
                                  End If
                              Else
                                  ' Close the reader object
                                  myReader.Close()
      
                                  channel.FilePlayer.Say("No entry in database. Press 1 to create a " + _
                                                         "new entry with this pin code", True)
      
                                  Dim menu As String = ""
                                  cause = channel.DtmfDetector.GetDigits(1, menu, 30)
                                  If cause = DtmfDetectorCause.Count Then
                                      If (menu(0) = "1") Then
                                          reply = CreateNewEntry(channel, digits, myConnection)
                                      End If
                                  End If
                              End If
                          Else
                              channel.FilePlayer.Say("No valid input detected")
                          End If
      
                          channel.FilePlayer.Say("Goodbye.")
                      End If
      
                  Catch ex As Exception
                      Me.Trace.TraceError("Exception thrown {0}", ex.Message)
                      reply = ReturnCode.ExceptionThrown
                  Finally
                      ' Close the database connection
                      If Not myConnection Is Nothing Then
                          myConnection.Close()
                      End If
      
                      ' Hangup the call
                      channel.HangUp()
                  End Try
      
                  Me.Trace.TraceInfo("Completed")
                  Return reply
      
              End Function
      
          End Class
      
      End Namespace
                                  

That's all...

In this tutorial you will have seen how to use a database system with an Aculab Cloud UAS application. Making queries, updating and inserting data are the fundamentals of databases. Complex queries, such as linking multiple tables together are not covered by this tutorial, but are certainly possible using the query commands mentioned above.