1. Managing MS SQL Server ® Data Sources in VS.NET ASP.NET

2. Data Source Processing Requirements In today's computer networks there needs to be the capability to share incompatible data from differing file types: – Data from different software companies such as Microsoft, Oracle, Sybase, Informix, etc. – Formatted data (i.e. currency format with 1000's separators), graphics, audio, video, etc. – Data from a variety of applications, i.e. word processing documents, spreadsheets, etc. – Data stored on intranets and the Internet including XML data sources

3. Universal Data Access The solution to this need to share data is called universal data access (UDA) At core to universal access is OLE (object linking and embedding) DB (database) object interface Data from a variety of sources can be shared across different applications and platforms Accesses data stored in different formats, i.e. – I.e., UDA can treat data stored in databases and spreadsheets as if they all were in the same format, even within the same application

4. Overview of the ADO.NET Framework ActiveX Data Object Model (ADO) – Provides objects that interface with the database – Separates the process of connecting to the data source from the manipulation of the data – Ability to write code that can transfer between applications

5. Visual Studio.NET and Databases Visual Studio.NET can operate on databases from different software companies: – Microsoft, Oracle, Sybase, Informix, etc. SQL commands are embedded into code enabling communication with the DBMS Additionally ASP.NET Toolbox controls may be used to provide database connectivity

6. General Steps for Using Web Databases 1.Build your database tables and queries/stored procedures 2.Create a connection to the database – The connection identifies the location of the database (the data source) and the connection method (ODBC driver, OLE-DB provider, or an OLE-DB.NET data provider), and any other settings, i.e. username/password 3.Create an ASP.NET Web page 4.Add ADO.NET connection object that connects to database, executes commands, and returns data from the database 5.Create code that will interact with the data, display the data in an ASP.NET control, perform calculations on the data, or upload changes to the database

7. .NET Data Provider

8. ADO.NET Data Provider Managed Providers or.NET Data Providers – ASP.NET application interacts with.NET objects – SQL Server.NET data provider is used to connect to a SQL Server database Native communication method to communicate so there is a performance improvement – OLE DB.NET data provider connect to any other data source accessed via the OLE DB interface

9. ADO.NET Data Provider (continued) ADO.NET Data Provider Objects – Connection – establishes a connection to the data source – Command – executes a command (SQL) – Parameter – send information with the command (retrieve only employees who live in Michigan) – DataReader – forward only, read only stream of data – DataAdapter – populates a DataSet DataSet – data disconnected from the database

10. .NET Managed Data Providers

11. ADO.NET Objects SQL Server.NET data provider – Prefix ‘Sql’ – SqlConnection, SqlCommand, SqlDataReader, SqlDataAdaptor OLE-DB data provider – Prefix ‘OleDb’ – OleDbConnection, OleDbCommand, OleDbDataReader, OleDbDataAdaptor. Within the Web page, ASP.NET data controls are usually bound to DataReaders or DataSets. – DataSet is exposed, so it doesn’t matter where the data came from, or what application it will be used in.

12. The ADO.NET Connection Object Provides the connection to the database – Requires a connection string Connection string – Provider – name of the managed provider. – Data Source - name of the server – User ID and Password - identifies authentication – Initial Catalog - name of the database

13. The ADO.NET Connection Object (continued) SQL Server Connection String Manually configured Data Connections window of Visual Studio.NET Single string or concatenate Dim CS As String CS = "Data Source=WindamereServer; User ID=sa; PASSWORD=; Initial Catalog=MyDatabase;"

14. The ADO.NET Command Object Identify command or a stored procedure – Connection - Connection used – CommandType - type of command Text - default, text string contains the command StoredProcedure – Name of a stored procedure – Stored procedures - commands that are stored within the database (compiled) TableDirect - specifies table to return

15. The ADO.NET Command Object (continued) CommandText – command to execute – Written in SQL - Structured Query Language Language used to identify what records to add, delete, or modify within the database Exposes a Parameters collection of objects – Used to apply values passed to stored procedures

16. The ADO.NET Command Object (continued) CommandText – command to execute – Written in SQL - Structured Query Language Language used to identify what records to add, delete, or modify within the database Exposes a Parameters collection of objects – Used to apply values passed to stored procedures – WHERE employeeState = “MI”

17. The ADO.NET Command Object (continued) ExecuteReader method – Method that ‘executes’ the command and passes the results to the DataReader object ExecuteNonQuery method – Does not return rows – Used to insert, modify, and delete data – Returns an integer of the number of rows affected – Perform SQL commands CREATE TABLE, INSERT INTO

18. The ADO.NET DataReader Object Deliver a stream of data from the database – High-performance – Read-only, forward-only stream of data Requires continual access to the database – Must remain connected until you have finished reading the stream of data

19. The ADO.NET DataReader Object (continued) Read – Returns single row and caches each row in memory only once – Mmoves current record pointer to the next record Close method – Closes the DataReader object and releases the references to the rowset CommandObject.CommandBehavior property – Closes the connection - CloseConnection

20. The ADO.NET DataReader Object (continued)

21. Figure 6-3 – Connection object provides ConnectionString – Command object provides SQL statements CommandType - Text CommantText - SELECT, which returns data ExecuteReader method provides DataReader as a result Parameter objects can be used

22. The ADO.NET DataReader Object (continued) Figure 6-3 (continued) – DataReader - receive the data Contains a collection of DataRows Read method to literally read through each row Use a looping structure to repeat through the rows. – Displaying the data - data controls

23. The ADO.NET DataReader Object (continued)

24. Figure 6-3 (continued) – Connection object provides ConnectionString – Command object provides SQL statements CommandType - Text CommandText - INSERT, which creates a new record ExecuteNonQuery method – returns number of rows affected Parameter objects can be used

25. The ADO.NET DataReader Object (continued) Figure 6-3 (continued) – DataReader object Contains information returned (number rows affected) No records are returned – no data binding to controls

26. The ADO.NET DataReader Object (continued)

27. The ADO.NET DataAdapter and DataSet Objects DataAdaptor object – Works with Connection object to connect to data – Provides bridge between DataSet and data source Commands to manage DataSet – Automatically generated via CommandBuilder object – SelectCommand - retrieve data – InsertCommand - add a new record – UpdateCommand - modify the data within a record – DeleteCommand - permanently remove a record

28. The ADO.NET DataAdapter and DataSet Objects (continued) Fill method - populates DataSet – Insert data SelectCommand returns into DataSet DataSet object – disconnected collection of one or more tables that are stored in memory on the server – maintains original set of data and changes – effectively a private copy of the database – does not necessarily reflect the current state

29. The ADO.NET DataAdapter and DataSet Objects (continued) DataSet Object – DataTableCollection Collection of one or more DataTable Objects Each DataTable consists of: – DataRowCollection and DataColumnCollection » store information about the rows and columns of data – ConstraintCollection » includes information about the primary and foreign keys, and constraint rules

30. The ADO.NET DataAdapter and DataSet Objects (continued) Primary key – No duplicate records appear in this column. Constraint rules – Field contains the correct datatype and values DataRelationCollection contains data required to maintain relationships between DataTables – Relationships can be made between DataTables – Tables are joined using the primary and foreign keys defined in the DataTable

31. The ADO.NET DataAdapter and DataSet Objects (continued)

33. Figure 6-3 – DataAdapter provides access to: Connection object provides ConnectionString Command object – in this case the commands are part of the DataAdapter (SelectCommand) DataAdapter populates DataSet – Can work with data while it’s in the DataSet, DataTables, or DataView – Bind DataSet, DataTables, or DataView to data controls within the Web page

34. The ADO.NET DataView Object Contains the data from the DataSet – Single DataTable or subset of records DataTable - DefaultView property – Returns all the records in the DataTable – Can select a subset of records from a table – Add columns to the DataColumnCollection RowFilter property - filter a subset Sort property - sort data based upon criteria in one or more of the columns

35. Data Related Namespaces

36. Building Database Connections Server Explorer window - access to local and network databases and data connections – Servers node Access to the services running on the computer, such as a database server – Data Connections node Data connection to a database Graphical tool used to create a database

37. Building Database Connections (continued) – ConnectString - connection properties – Database property - database – Type property - database application – Driver - ODBC driver, OLE-DB provider, or.NET managed data provider – State - if database is currently connected – User Name of user account that created database Creator is database owner, or dbo

38. Building Database Connections (continued) Server property - server – Default name MSDE/SQL Server is [MachineName]\NetSDK MachineName - name of your local computer (local)\NetSDK or localhost Driver/Provider – Assumed to be SQL Server if it uses the SQLClient class - not required in the Connection String

39. Downloading Microsoft SQL Server Desktop Engine (MSDE) Files 1.Create folder – md c:\MSDETempDE – Download files and extract files Download files 2.Command Window – cd C:\sql2ksp3\MSDE – setup INSTANCENAME="NetSDK" SECURITYMODE=SQL SAPWD="password" 3.Verify files and folders installed – C: cd\Program Files\Microsoft SQL Server\MSSQL$NETSDK – Binn, Data, Install, and Log folder should be there

40. Installing.NET Framework DSK Samples Databases 1.Click Start and select "All Programs"  "Microsoft.NET Framework SDK v1.1"  "Samples and Quickstart Tutorials" 2.Select "Setup the Quickstarts" and in the download window click button; click again (ConfigSamples.exe will not harm your computer) 3.When "Congratulations!" window opens, click the button, then the button (if the page loads, installation was successful)

41. Visual Studio.NET Built-In Database Tools Visual tools to create and manipulate databases – Server Explorer—established database connections, creates database, tables, and stored procedures – Table Designer—create columns in tables, view and edit table data – Query and View Editor—graphically create database queries, and view results – SQL Editor—create and edit SQL scripts and stored procedures, and view results – Data Diagram—graphically define relationships between columns in two or more tables

42. Creating a SQL Server Database in Visual Studio.NET Authentication is required for access – Windows NT – SQL Server User ID identifies users and access to objects – Each user has roles - create or modify data object – Needs permission to create database See Appendix B for working with the MSDE and troubleshooting data connection problems

43. The Table Designer (Page 1) Table Design view – Create schema or table structure in the Design pane Column Name (fieldname)—do not use blank spaces or special characters other than an underscore Data Type—convert to.NET data types when you retrieve your data using ADO.NET Allow Nulls—no value, a null value is returned – Properties Pane—below the Design pane; available options depend upon field's data type Table Data view – Edit table data (create new row, modify or delete rows)

44. The Table Designer ("Products" Table)

45. The Table Designer (Page 2) Properties Pane entries for the int data type – Identity property, when set to a value of "Yes", automatically provides a unique value for each record to locate a specific row of data – Identity Seed—shows the initial value of first row – Identity Increment—value by which to increment the seed each time a new row is added – Therefore: If seed is 1 and increment is 1, field values for the first three records are 1, 2, 3… If seed is 1 and increment is 2, field values are 1, 3, 5…

46. The Properties Pane

47. The Table Designer (Page 3) Primary Key – Each value must be unique within this column All rows must have a value for this column No record contains a null value for column – Click the Row selector box; then click the "Set Primary Key" icon on Table toolbar – A yellow "key" icon appears at the side of the column name(s)

48. The Table Designer ("Products" Table)

49. The Table Designer (Products Table)

50. Creating a View with Query and View Editor (Page 1) Used to create a query in the database When one pane changes, the other panes updated – Table Pane—add tables and select columns (displays the query visually with icons ) – Grid Pane—select columns and criteria, just when using Microsoft Access; column name and table indicate where to retrieve the values for column – SQL Pane—generates and displays corresponding SQL statement – Preview Pane—test run queries and displays results

51. Creating a View with Query and View Editor

52. Creating a View with Query and View Editor (Page 2) The Grid pane elements: – Alias—display an alternate column name (useful for calculated or concatenated columns) – Output—should column be visible or not (some columns may be used only for criteria conditions) – Sort type—ascending or descending – Sort order—sorting hierarchy (indicate one or more columns to sort the results) – Criteria—conditional statement (more than one entry indicates an AND condition) – Or—indicates an alternative condition

53. Setting Relationships with Data Diagram Defines relationships (links) between tables – A line is drawn from a field from one table to another which indicates the fields that define the relationship – Referential integrity The value of any row in the linked column of one table must match a primary key value in the other, or be null Endpoints indicate type of relationship – One-to-many relationship Key at one endpoint and infinity symbol at the other – One-to-one relationship Key at each endpoint

54. Setting Relationships with Data Diagram Foreign key Primary key

55. Building Stored Procedures (Page 1) A stored procedure is a SQL script (command) that is stored within the database: – Runs a SQL query (SELECT, INSERT, etc) – Because stored procedures already have been parsed and compiled by the server, they are more efficient than a SQL statement in a View – Values can be replaced with input parameters (represent variable values entered by user)

56. Building Stored Procedures (Page 2) When a new procedure is begun, the editor inserts a skeletal stored procedure (template) Color codes the SQL keywords in blue Comments are contained within /* and */ characters and displayed in green text The default behaviors of the editor may be changed in the Options… dialog window on the Tools menu – Tab size, word wrapping, line numbers, etc.

57. Building Stored Procedures (Page 3)

58. CREATE PROCEDURE dbo.sp_ReorderProducts /* ( @parameter1 datatype = default value, @parameter2 datatype OUTPUT ) */ AS SELECT * FROM Products WHERE QuantityAvailable < MinOnHand /* SET NOCOUNT ON */ RETURN

59. The CREATE and ALTER Procedures When new procedure is being created, first statement is CREATE PROCEDURE The first line changes from CREATE PROCEDURE to ALTER PROCEDURE after the procedure has been created and saved (compiles when saved) Developer may change or alter the procedure using the ALTER PROCEDURE command

60. Modifying Stored Procedures with the SQL Query Builder The SQL Query Builder is a tool within the Stored Procedure application It functions just like the Query and View Editor used for creating and editing views To use the SQL Query Builder 1.Select the Edit Stored Procedure command for an existing procedure 2.Right-click around the block of SQL code enclosed within the blue lines and select Design SQL Block 3.Use the Query and View editor as before

61. Data Retrieval in SQL The keyword SELECT is used in SQL to create queries that retrieve sets of rows (records) from one or more related tables in a relational database Basic format: SELECT columnName(s) FROM tableName(s) WHERE relationCondition; – SELECT clause is a comma-delimited list that limits columns returned (required) – WHERE clause is a condition that limits rows returned (optional)

62. The WHERE Clause Base on a truth condition which limits which rows are returned in the query Relational operators are =, >, =, Examples: SELECT * FROM Payables WHERE [PO number] = "10003"; SELECT * FROM [Purchase Order] WHERE Subtotal >= 38.15;

63. Building Stored Procedures

64. Input Parameters in Stored Procedures (Page 1) Variable values passed to the stored procedure – Parameters are input parameters by default – Must match data type and length of the field that it references in the SQL query – Name always begins with the symbol "@" – The input parameter is often compared to a value in a SQL WHERE clause A default value can be provided – Must be a constant (not a variable) or it can be NULL – Wildcard characters (*) are permitted

65. Input Parameters in Stored Procedures (Page 2)

66. CREATE PROCEDURE dbo.sp_DisplayProduct @param_ModelName nvarchar(50) /* ( @parameter1 datatype = default value, @parameter2 datatype OUTPUT ) */ AS SELECT ProductID, ModelName, UnitCost, ModelNumber, ProductImage FROM Products WHERE ModelName = @param_ModelName /* SET NOCOUNT ON */ RETURN

67. Input Parameters in Stored Procedures

68. Output Parameters in Stored Procedures Send values back to the object that called stored the procedure – ReturnValue—a return value is passed back – Called with RETURN keyword – Retrieves identity column value (the primary key) Return @@Identity Information such as number of records affected – Values can be integer, money, varchar - not text

69. The SQL INSERT Statement (Page 1) The INSERT command adds a row (record) to a table Format INSERT INTO tableName [(columnNames)] VALUES (value_list …); Example (values must match the number of items and data types in the original table): INSERT INTO Payables VALUES ("10004", ”650", 1000, 3,.F.);

70. The SQL INSERT Statement (Page 2) Example (null values may be indicated by leaving space between commas where they occur in table): INSERT INTO Payables VALUES ("10004", "701",, 8,.F.); Example (a columnName list may be used if not all columns will be assigned a value): INSERT INTO Payables, ([PO number], [Product number], Quantity, [Back ordered?]) VALUES ("10004", "701", 8,.F.);

71. Insert Stored Procedure with Parameter

72. CREATE PROCEDURE dbo.sp_InsertCat @param_CatName nvarchar(50) /* ( @parameter1 datatype = default value, @parameter2 datatype OUTPUT ) */ AS INSERT INTO Categories (CategoryName) VALUES (@param_CatName) /* SET NOCOUNT ON */ RETURN @@Identity

73. Insert Stored Procedure with Parameter

74. WHERE with the LIKE Operator (Page 1) Uses the symbol "%" as a wildcard to substitute for any other character(s) in a WHERE clause Format: SELECT columnNames FROM tableName WHERE columnName LIKE "%criteriaString%"; – One or more wildcard symbols may be inserted at beginning middle or end of criteriaString

75. WHERE with the LIKE Operator (Page 2) Example 1 (begins with the letter "P"): SELECT * FROM Product WHERE Product LIKE "P%"; Example 2 (contains the letter "R"): SELECT * FROM Product WHERE Product LIKE "%R%";

76. WHERE with the LIKE Operator (Page 3)

77. CREATE PROCEDURE dbo.sp_SearchProducts @param_SearchProducts nvarchar(50) /* ( @parameter1 datatype = default value, @parameter2 datatype OUTPUT ) */ AS SELECT ProductID, ModelName, ModelNumber, UnitCost, ProductImage, Manufacturer FROM Products WHERE ModelNumber LIKE = '%' + @param_SearchProducts + '%' OR ModelName LIKE = '%' + @param_SearchProducts + '%' OR Description LIKE = '%' + @param_SearchProducts + '%' OR Manufacturer LIKE = '%' + @param_SearchProducts + '%' /* SET NOCOUNT ON */ RETURN