Transcript Update Database

Introduction to ADO.Net and Visual
Studio Database Tools
ISYS 512
Database Processing
• Querying database
• Updating database:
– Insertion, deletion, modification
Steps to Retrieve Data
• Establishes a connection to the database.
• Executes query commands against the
database.
– SQL Select commands
• Process the returned data.
Steps to Update Data
• Establishes a connection to the database.
• Executes update commands against the
database.
– SQL Insert, Delete, Update commands
• Receive confirmation of completion.
ADO.Net: Connected and Disconnected
Data Processing
• The ADO.Net environment can be categorized
into connected and disconnected environments.
– A connected environment requires a constant
connection to transfer data between the client
application and the data source.
– A disconnected environment retrieves data and
performs modification without a constant connection
to the data source.
ADO.Net Classes
ADO.Net Classes and Data Consumer
Ado.Net
Adapter
Connection
Dataset
Data Consumer
Command
WinForm
DataReader
WebForm
ADO.NET Objects
• Connection Object: Represent a connection to the
database.
• Command Object: The command object allows us
to execute a SQL statement or a stored procedure.
• DataReader: It is a read-only and forward-only
pointer into a table to retrieve records.
• DataSet Object: A DataSet object can hold several
tables and relationships between tables.
• DataAdapter: This the object used to pass data
between the database and the dataset.
Data Providers
• ODBC Provider
– Open Database Connectivity
• A driver manager
• Used for relational databases
• OLE DB Provider
– OLE DB interfaces provide applications with uniform access to
data stored in diverse information sources, or data stores.
– MS Access (accdb)
• SQL Server Provider
• Oracle Provider
• Etc.
Using ODBC
• Windows 7:
• Control Panel /Administrative Tools/DataSource(ODBC)
• Three types of data source names, DSN
– User DSN: usable only by you and only on the machine
currently using.
– System DSN: Any one using the machine can use.
– File DSN: Can be copied and used by other computers
with the same driver installed.
• Note: For 32 bit software, you have to open the
ODBC panel from
C:\Windows\SysWOW64\odbcad32.exe
Define an ODBC DSN for Access
Database
• Download: SalesDB2011.accdb
• Open ODBC Window
• Define a System DSN to SalesDB2011 and
name it: MySalesData
SQL Server Express/
SQL Server Express LocalDB
• SQL Server Express is available free from
Microsoft, but it requires more computer
resources.
• SQL Server Express LocalDB is a lightweight version of SQL Server Express that is
already installed with VS 2013.
VS Database Tools
• View/Server Explorer:
– For connection to ODBC data sources, OleDB to
MS Access, and SQL Server Express
• View/SQL Server Object Explorer
– For connection to SQL Server LocalDB
Connect to Access Database using OLE DB
• From Server Explorer, right-click Add Connection:
– Microsoft Access Database File (OLE DB)
– Browse for database
– Test Connection
• Tools/Connect to database
Connect to Access Database using ODBC
• From Server Explorer:
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right-click Add Connection
Click Change
Microsoft Access ODBC Data source
Select DSN from the dropdown list
Test Connection
Working with SQL Server Express LocalDB
• View/SQL Server Object Explorer
• Point to SQL Server and Right-click:
– Add SQL Server
• Connect to Server
– Serve name: (localdb)\Projects
– Connect
Lab: Creating a LocalDB
Database
• Database Name: MyDept
• Tables:
– Department:
• DID, Dname, Office
– Employee
• EID, Ename, Sex, Salary, HireDate, DID
To Add a New Database
• Open the LocalDB node
• Right-click Databases
– Add new database
• Enter database name
– Example: MyDept
To Add a New Table: Department
• Open the Database node: Open the MyDept node
• Right-click Tables and select: Add New Table
• Change the table name to Department
– CREATE TABLE [dbo].[Department]
• Define fields
• Click Update
• Click Update Database
To Add Records
• Open the Tables node
• Right-click the table name (Department)
and select View Data
To Modify Table Design
• Point and right-click the table name:
– Select: View/Designer
• Change the CREATE TABLE command
• Or Change the design with the designer
Add Employee Table
• Right-click Tables and select Add Table:
– EID, Ename, Sex, Salary, HireDate, DID
• Add records
Three Ways to Create ADO.Net Objects
• 1. Automatically generated when
creating data bound form.
– Form wizard
• 2. Using Data Adapter Wizard
• 3. Using code:
– Example:
– string strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data
Source=C:\\CSharpexamples\\SalesDB2011.accdb";
– OleDbConnection objConn = new OleDbConnection(strConn);
– objConn.Open();
Data Binding
• Connect a control or property to one or more data
elements.
• Simple binding: Use simple binding to display a
field value in controls that show Data Bindings in
the property window, such as text box or label.
• Complex binding: Use complex binding to bind
more than one field to controls such as DataGrid
and list box. Use the control’s Data Source and
Data Member to bind the data.
Automatically Generating Data
Bound Form
• Creating a form with ADO.Net objects and databound controls to display and update information in
a dataset.
• Step 1: Add a new data source:
• Step 2: Select controls for table fields:
– Click the dropdown list next to the table’s name:
• Datagrid view
• Details
• Step 3: Drag the table to form.
Add Data Source
• Data Source window:
– View/Other windows/Data Source
• Add New Data Source
– From Dataset
– Select connection
– Select tables
Data Bound Form Examples
• Using the LocalDB database MyDept, show
records of the Employee table:
– with dataGridView
– with detail view
Items Added to the Form
• Table Adapter: click smart tag
– Add query
– Preview data
• Dataset:
– Edit in dataset designer
• Binding Source: It is an object that keeps track of
position (the current row) of a data source.
– Preview data
• Code view:
– Form load event:
• Adapter’s Fill command
Other Data Form Demos
• DataGrid View
• Add /Modify/Delete records.
• Read only form:
– Delete AddNew, Delete, Save buttons from
navigator bar.
Hierarchical Forms:
Department/Employees
• Parent table/Child table
– Add parent table and child table to Data Source
– Drag the parent table and the child table to the form.
Parent table uses detail view and child table uses
dataGrid view
– Click Dataset object’s smart tag to choose Edit in
Dataset Designer
– With the designer, right click the parent table and
choose Add/Relation
– Change dataGrid’s DataSource property to the relation
(shown under the parent table’s binding source).
Detail Form with Bound ListBox
• Example: Employee table form with EID listbox
and displays selected employee information in
textboxes.
– Choose detail view for the Employee table.
– Click the dropdown list next to the EID field and click
ListBox
– Drag the Employee table to the form.
– Bind the EID field to the BindingSource:
• Activate the Property window and click the listbox
• Set the DataSOurce property to BindingSource
• Set the Display Member property to EID
Creating A Database Application
Without Programming
• Creating a database application to display
information and update database.
• A main form with buttons to open data
forms:
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DisplayInfo
Enter New
Modify
Exit