DD Class9

review Bios and Logon

Second Normal Form

In order to reach 2NF the table must first be in 1NF

Second Normal Form eliminates functional dependencies on a partial key by putting the fields in a separate table from those that are dependent on the whole key.

'Remove Fields that are not dependent on the primary key'

Not Normal

Adresses

CustNum	FirstName	LastName	Address	City	State	ZIP
1	John	Doe	12 Main Street	Sea Cliff	NY	11579
2	Alan	Johnson	82 Evergreen Tr	Sea Cliff	NY	11579
3	Beth	Thompson	1912 NE 1st St	Miami	FL	33157
4	Jacob	Smith	142 Irish Way	South Bend	IN	46637
5	Sue	Ryan	412 NE 1st St	Miami	FL	33157

Normal

StatesZips

ZIP	City	State
11579	Sea Cliff	NY
33157	Miami	FL
46637	South Bend	IN

Address

CustNum	FirstName	LastName	Address	ZIP
1	John	Doe	12 Main Street	11579
2	Alan	Johnson	82 Evergreen Tr	11579
3	Beth	Thompson	1912 NE 1st St	33157
4	Jacob	Smith	142 Irish Way	46637
5	Sue	Ryan	412 NE 1st St	33157

In class

Normalize the books exmaple

Books

Author	Title	Pages	Publisher	PublisherURL	Subject	ISBN
Michael Allen Dymmoch	The Man Who Understood Cats	256	Avon Books	http://www.harpercollins.com/imprints/index.aspx?imprintid=517994	Fiction Mystery	0380722658
Joseph Cancellaro	Exploring Sound Design for Interactive Media	272	Thomson Delmar Learning	http://www.delmarlearning.com/	Sound	1401881025

Third Normal Form

Third Normal Form eliminates functional dependencies on non-key fields by putting them in a separate table. At this stage, all non-key fields are dependent on the key, the whole key and nothing but the key. Must be in second normal form.

Not normal

Company	City	State	ZIP
Acme Widgets	New York	NY	10169
ABC Corporation	Miami	FL	33196
XYZ, Inc.	Columbia	MD	21046

Normal

KompanyID	KompanyName	Zip
1	Acme Widgets	10169
2	ABC Corporation	33196
3	XYZ, Inc.	21046

Zip	CityID
10169	1
33196	2
21046	3

CityID	City
1	New York
2	Miami
3	Columbia

StateID	State
1	NY
2	FL
3	MD

http://home.earthlink.net/~billkent/Doc/simple5.htm.

Many to Many Relationships

Look up tables. Are often used to define a many to many relation ship. These lookup tables often have a compound key.

See the Student Courses example from the Data Relationships page.

This is a demonstration of a logon system where users can have multiple roles. There is a compound key used on the roles table. The compound key consists of two or more foreign keys. Each combination of foreign keys must be unique.

Home Work

• Create the tables necessary for user authentication
• Logon example script
  

  Logon Script Diagram
  • People
  • Roles
  • RoleTypes

• Create a form that queries your tables (you should use a view to join the roles)
  • If logon was successful show user roles
  • If logon was not, do not show user roles

• Think about Ideas for a final project

Logon

Insert into the People Table

<sql> INSERT into People (salutationID, firstName, lastName, logonName, passwd) values (1, 'jeff', 'meyers', 'jmeyers', 'monkey') </sql>

Check the new users PeopleID

<sql> SELECT PeopleID from People WHERE firstName = 'jeff' and lastName='meyers' and logonName='jmeyers' </sql>

results PeopleID = 1

Give the new user a Role by inserting the PeopleID and a roleID into the roles table

<sql> INSERT into roles ( PeopleID, roleTypeID, RoleActive ) values ( 1, 1, 1) </sql>

 Note that we need two INSERT statements to create a working account and role. Since these two statements
depend on each other and we will be left with an Person without a role or a role without a person if one 
statement fails the entrire operation should be wrapped in a transaction. More on this next week...

Now we have a user and that user has a role. We need to be able to read back the userName, passowrd, roleActive and roleTypeName in order to check if a user is valid.

The easiest way to do this is with a view

<sql> SELECT dbo.people.peopleID, dbo.people.firstName, dbo.people.lastName, dbo.people.logonName,

      dbo.people.passwd, dbo.peopleSalutationTypes.salutationID, 
      dbo.peopleSalutationTypes.salutation, dbo.roles.roleActive, dbo.roleTypes.RoleTypeID,
      dbo.roleTypes.RoleTypeName, dbo.roleTypes.RoleTypeHier, 
      dbo.roleTypes.roleTypeActive

FROM dbo.people INNER JOIN

      dbo.peopleSalutationTypes ON dbo.people.salutationID = dbo.peopleSalutationTypes.salutationID 

INNER JOIN

      dbo.roles ON dbo.people.peopleID = dbo.roles.PeopleID 

INNER JOIN

      dbo.roleTypes ON dbo.roles.RoleTypeID = dbo.roleTypes.RoleTypeID

</sql>

Now we can use the view to test a logon SELECT statement <sql> SELECT peopleID, firstName, lastName, logonName, passwd, salutationID,

      salutation, roleActive, RoleTypeID, RoleTypeName, RoleTypeHier, 
      roleTypeActive

FROM logon_vw WHERE logonName = 'jmeyers' and passwd = 'monkey' and

       roleActive = 1 and

roleTypeActive = 1 </sql>

Now that we have the DataBase working correctly we can move on to the c#

Sessions

Every web application has a collection of objects called a session. Each browser is assigned a unique cookie that is used to identity the SessionID of the connection.

The session collection can hold any object and remain until a session times out. A session times out when the web server does not receive a request from a client for longer than the timeout period (deafult 20 mins)

session variables are set just like any other Collection. When you retrive an item form the collection you need to cast it back to it's original type (string casts are implict in c# so you really don't have to cast a string).

<csharp> Session["LogonName"] = "test";

string strLogonName = (string)Session["LogonName"]; </csharp>

Review ADO

• Connection - used to connect the data consumer ASP.NEt to a Data Provider
• Command - used to issue SQL commands to a Data Provider
• DataReader - A fast forward only DataSet that holds one or more resultsets.Fast and efficient
• DataSet - can contain multiple tables and relationships between tables
• DataAdapter - Passes Data from a Connection object to a DataSet and updates that data. ( A bridge used to fill dataSets with DataAdapter.Fill and DataAdapter.Update)
• DataTable - structure that holds a set of rows and columns
• DataRelation - holds relations between DataTables in a DataSet
• DataRow - data within data row
• DataView - a specific view of the DataTables within a Dataset

Connection
DataAdapter	DataReader
DataSet DataTable DataView DataRow DataRow DataRow DataTable DataRow DataRow DataRow DataTable DataRow DataRow DataRow

Template:ADO.NET Diagram

Simple ADO Binding

<csharp> //Connection string comes from web config

       SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["IamConnectionJeff"].ConnectionString);             
       
       string strSQL = "Select * from Course";  
       
       SqlCommand dc = new SqlCommand(strSQL , conn);
       SqlDataAdapter da = new SqlDataAdapter(dc);
       DataSet ds = new DataSet();
       DataTable dt = new DataTable();
       
       da.Fill(ds, "Course");          //Use the DataAdapter to fill the DataSet with a named Table
       dt = ds.Tables["Course"];       //Retreive the named table from the DataSet
       
       gvTestOrig.DataSource = dt;     //Set the DataTable as the source for the GridView noe AutoGenerateColumns = true
       gvTestOrig.DataBind();          //Bind the data form the table to the GridView

</csharp>

The above code binds to a control called gvTestOrig

<csharp>

<asp:GridView ID="gvTestOrig" runat="server" AutoGenerateColumns="true" />

</csharp>

http://iam.colum.edu/dd/classsource/class8/SimpleADO.aspx - source

Same code but I moved some of the code into a function and split the declareation and initialization of some object to that they are scoped to the page not to Page_Load. This allows other functions on the page to use these objects.

http://iam.colum.edu/dd/classsource/class8/ADOTest1.aspx - source

Inserting Editing Deleteing With ADO

Add to a DataTable <csharp>

       DataTable dt = ds.Tables["Course"];
       DataRow dr = dt.NewRow();
       dr["CourseName"] = "Applcations Design";
       dr["CourseNumber"] = "36-3601";
       dt.Rows.Add(dr);

</csharp>

Modify and DataTable <csharp>

       DataTable dt = ds.Tables["Course"];
       DataRow dr = dt.Rows[3];            //Hack hard coded index
       dr["CourseName"] = "Application Design";
       dr["CourseNumber"] = "36-4601";

</csharp>

Delete from a DataTable <csharp>

       DataTable dt = ds.Tables["Course"];
       DataRow dr = dt.Rows[1];            //Hack hard coded index
       dt.Rows.Remove(dr);

</csharp>

There are better method to select which row to modify see the example below

http://iam.colum.edu/dd/classsource/class8/ADOTest2AddModifyDelete.aspx - source

notice that changes made to the DataSet are not synchronized back to the Data Provider. 
The DataAdapter is able to sync these changes, remeber that the DataAdapter acts as a bridge between the 
DataSet and the DataProvider.

The DataAdapter can use the SqlStringBuilder class to create select, update, and delete statements. Once these statements are built the DataAdapter can update the DataProvider.

<csharp> //Uses an SqlBuilder to update the DataAdapter also displays the generated sql in a lable

   public void CommitChanges()
   {
       //Get a stringBuilder from out DataAdapter
       SqlCommandBuilder cb = new SqlCommandBuilder(da);
       da.UpdateCommand = cb.GetUpdateCommand();
       lblUpdateCommand.Text = da.UpdateCommand.CommandText;   //Display the update Command in a Label
       da.Update(ds.Tables["Course"]);         //User tha DataAdpater to update the Data Provider
   }

</csharp>

http://iam.colum.edu/dd/classsource/class8/ADOTest3Commit.aspx - source

Homework

1 Build a page that demonstrates a single table update with ADO,

2 Write a proposal for final project the proposal should include

Proposal Template: http://iam.colum.edu/janell/edu/wi/docs/proposal_wi.rtf

Proposal Template (pdf): http://iam.colum.edu/janell/edu/wi/docs/proposal_wi.pdf

• Purpose
• Objectives
• Audience

• Website Scope
  • Simple map of web site(can be on paper or hyperlinks)
  • Number of web pages
  • Function of web pages
• DataBase Design
  • Mock up of tables and relations
  • ERD on paper or diagram in sql