Difference between Windows Application and Web
Application?
Windows Application:
Ø Windows Applications Doesn’t Have Server tags
Ø Windows Applications Always runs on personal computers and work stations.
Ø Windows Applications extension .Exe
Ø window based app. need to be
install on your machine to access
Ø windows applications (desktop)
need to be installed on each client's PC.
Ø
Windows
application runs faster than Webapplication.
Ø Windows application have many
inbuilt classes in .Net compared to Web application.
Web Application:
Ø Web Applications Having Server tags
Ø Web application or webapp is an
application that is accessed via Web browser over a network such as the
Internet or an intranet
Ø Always Run in URL
Ø
Web
applications are very much useful when they are hosted.Web app. can be access
from anyware in the world through the internet.
Ø
Web
application is tested mainly for browser compatibility and operating system
compatibility, error handling, static pages, back-end testing and load testing.
5)Web applications are programs that used to run inside some web server (e.g., IIS) to fulfill the user requests over the http.
5)Web applications are programs that used to run inside some web server (e.g., IIS) to fulfill the user requests over the http.
Ø Common Web applications include
Webmail, online retail sales, online auctions, wikis, discussion boards,
Weblogs
Write The Connection String in c# Language?
Web.Config file:
<connectionStrings>
<add name="ASDF"
providerName="System.Data.SqlClient"
DataSource="xxx,1433;Integrated
Security=True;User ID=sa;Password=123456" />
</connectionStrings>
Web.Config file to Aspx.cs page:
String
XXX=System.configarationmanager.connectionstring[“asdf”].tostring();
OR
SqlConnection
con=new SqlConnection(“DataSource="xxx,1433;Integrated
Security=True;User ID=sa;Password=123456"”);
Write The Select Command In SqlServer?
Ø The SQL SELECT statement is used to retrieve records from one
or more tables in your SQL database.
Example:
Ø Select
* From Table_Name
OR
Ø SELECT column_first,column_second
FROM table_name;
FROM table_name;
Difference between update command and alter
command with examples?
Update:
Ø Used to update
existing records in a Database
Ø It is a DML
Command, means commands that are used to manage data without altering the DB
Schema are called DML statements
Example:
Syntax:
UPDATE
Table_name SET Col1name=value1, col2name = val2, WHERE ColXname
= some value
Alter:
Ø Used to modify,
delete or add a column to an existing table in a Database
Ø It is a DDL
command, means commands that are used to define the structure of a DB (DB
Schema) are called DDL statements
Example:
Syntax:
Ø ALTER TABLE
Table_name
ADD newColname
dataTypeofNewCol or to delete a col
DROP Colname or change
datatype of an existing col in table
ALTER Column Colname newDatatype
Difference
between image control and image button control in asp.net?
Image
Button:
Ø ImageButton control is generally used to post the form or fire an
event either client side or server side. When it is rendered on the page,
generally it is implemented through <input type=image > HTML tag.
Prooerty
And Descriptions:
Ø Specifies that the control is a server
control. Must be set to "server"
Ø ImageUrl: Gets or Sets the
location of the image to display.
Ø PostBackUrl: Indicates the URL on which the Form will be posted
back.
Ø OnClick: Attach a server side method that will fire when button will
be clicked
Ø OnClientClick: Attach a client side (javascript) method that will
fire when button will be clicked.
Ø
Image:
Ø The Image control is used to display an image.
Property And Description:
Ø DescriptionUrl: The location to a detailed
description for the image
Ø Runat: Specifies that the control is a server
control. Must be set to "server"
Difference between check box and
radio buttons?
check box:
Ø Checkboxes may be switched independently of each
other
Ø The checkbox control is used to display a check
button.
Ø Check box : you can used it singly.
Ø A checkbox is square and you can check as many as
you want.
Ø Check box is used to indicated a boolean value:
True or False
Ø Multi-Select (Checkbox) based questions allow
users to choose more than one option for the same question. This is used when
the intent of the question has a "select all that apply."
radio buttons:
Ø radio buttons are part of a group where only one
may be active at a time.
Ø The RadioButton control is used to display a
radio button.
Ø Radio Box: if you want to make a multiple choice
in your program such as in the Options dialog of you program. For example, you
want user to choose between "Save work into file" or "Save work
into memory", you can apply with Radio Box.
Ø A radiobutton is round and you can just check one
per group.
Ø A groupe of Radio Buttons is used when you have
more choices than True or False... say you have a choice like
"Maybe".
Ø Single-Select (Radio) based questions allow
users only to choose one (and only one) option for any given question. This is
used when the intent of the question is "select one."
7) Explain About constraints with example?
Constraints in a database maintain the integrity of the
database.
RDBMS Stands for (Relational dataBase
management System)
Constraints enable the RDBMS enforce
the integrity of the database automatically, without needing you to create
triggers, rule or defaults.
Types of constraints:
--> PRIMARY KEY
--> UNIQUE
-->FOREIGN KEY
--> CHECK
--> NOT NULL
A PRIMARY KEY constraint is a unique
identifier for a row within a database table. Every table should have a primary
key constraint to uniquely identify each row and only one primary key
constraint can be created for each table. The primary key constraints are used
to enforce entity integrity.
A UNIQUE constraint enforces the
uniqueness of the values in a set of columns, so no duplicate values are
entered. The unique key constraints are used to enforce entity integrity as the
primary key constraints.
A FOREIGN KEY constraint prevents any
actions that would destroy link between tables with the corresponding data
values. A foreign key in one table points to a primary key in another table.
Foreign keys prevent actions that would leave rows with foreign key values when
there are no primary keys with that value. The foreign key constraints are used
to enforce referential integrity.
A CHECK constraint is used to limit
the values that can be placed in a column. The check constraints are used to
enforce domain integrity.
A NOT NULL constraint enforces that
the column will not accept null values. The not null constraints are used to
enforce domain integrity, as the check constraints.
You can create constraints when the
table is created, as part of the table definition by using the CREATE TABLE
statement
Example
CREATE TABLE employee(
EmployeeId INT NOT NULL,
LName VARCHAR(30) NOT NULL,
FName VARCHAR(30) NOT NULL,
Address VARCHAR(100) NOT NULL,
HireDate DATETIME NOT NULL,
Salary MONEY NOT NULL CONSTRAINT check_sale CHECK (salary > 0)
)
ALTER TABLE employee
ADD CONSTRAINT pk_employee PRIMARY
KEY (EmployeeId)
ALTER TABLE employee
DROP CONSTRAINT pk_employee
Types of constraints
I focus on four types of constraints:
primary key, foreign key, unique, and check. Here's a brief overview of each.
Primary key
This constraint is used to guarantee
that a column or set of columns on a table contain unique values for every
record in the given table. This lets you ensure data integrity by always being
able to uniquely identify the record in the table.
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A table can have only one primary key
constraint defined on it, and the rows in the primary key columns cannot
contain null values. A primary key constraint can be defined when a table is
created, or it can be added later.
This script creates a primary key
constraint on a single field when the table is created:
IF OBJECT_ID('SalesHistory')>0
DROP TABLE SalesHistory;
GO
CREATE TABLE [dbo].[SalesHistory](
[SaleID] [int] IDENTITY(1,1) NOT NULL PRIMARY KEY,
[Product] [char](150) NULL,
[SaleDate] [datetime] NULL,
[SalePrice] [money] NULL
)
GO
The followings script creates the
primary key constraint when the table is created. This method allows you to
define a name for the constraint and to create the constraint on multiple
columns if necessary.
IF OBJECT_ID('SalesHistory')>0
DROP TABLE SalesHistory;
GO
CREATE TABLE SalesHistory(
SaleID int IDENTITY(1,1) NOT NULL,
Product char(150) NULL,
SaleDate datetime NULL,
SalePrice money NULL,
CONSTRAINT pk_SaleID PRIMARY KEY (SaleID)
)
GO
This script creates the primary key
constraint on the table after it is created:
IF OBJECT_ID('SalesHistory')>0
DROP TABLE SalesHistory;
GO
CREATE TABLE SalesHistory(
SaleID int IDENTITY(1,1) NOT
NULL,
Product char(150) NULL,
SaleDate datetime NULL,
SalePrice money NULL
)
GO
ALTER TABLE SalesHistory
ADD CONSTRAINT pk_SaleID PRIMARY KEY (SaleID)
GO
Foreign key
This constraint limits the values of
columns in one table based upon the values of columns in another table. This
link between the two tables requires the use of a "lookup table,"
which contains the accepted list of values; this list must contain a unique or
primary key constraint. After the constraint is established between the two
tables, any data modifications to the fields defined in the constraint on the
foreign key table will cause a validation to ensure that the data being updated
or inserted is contained in the lookup table.
The script in Listing A creates a
ProductTypes table, which will serve as the lookup table and the SalesHistory
table, which will reference the ProductID in the ProductTypes table. If I had
excluded the constraint definition in the table declaration, I could go back
later and add it. You can do this with the script in Listing B.
The previous script contains the WITH
NOCHECK clause. I use it so that any existing values in the table are not considered
when the constraint is added. Any records in the table that violate the newly
added constraint will be ignored so that the constraint is created. The
constraint will only be applicable to new records entered into the SalesHistory
table.
Unique
This constraint guarantees that the
values in a column or set of columns are unique. Unique and primary key
constraints are somewhat similar because each provide a guarantee for
uniqueness for a column or set of columns. A primary key constraint
automatically has a unique constraint defined on it.
There are two differences between the
constraints: (1) You may have only one primary key constraint per table, yet
you may have many unique constraints per table; (2) A primary key constraint
will not allow null values but a unique constraint will (although it will only
allow one null value per field).
This script creates a unique
constraint on the SaleID column when the table is created:
IF OBJECT_ID('SalesHistory')>0
DROP TABLE SalesHistory;
GO
CREATE TABLE [dbo].[SalesHistory](
[SaleID] [int] NOT NULL UNIQUE,
[Product] [char](150) NULL,
[SaleDate] [datetime] NULL,
[SalePrice] [money] NULL
)
GO
The following script creates a unique
constraint on the table at creation, and it allows for constraint naming and
for defining the unique constraint on multiple columns if necessary.
IF OBJECT_ID('SalesHistory')>0
DROP TABLE SalesHistory;
GO
CREATE TABLE [dbo].[SalesHistory](
[SaleID] [int] NOT NULL,
[Product] [char](150) NULL,
[SaleDate] [datetime] NULL,
[SalePrice] [money] NULL,
CONSTRAINT uc_SaleID UNIQUE (SaleID)
)
GO
This script creates the unique
constraint on the SalesHistory table by altering the table after it has been
created:
IF OBJECT_ID('SalesHistory')>0
DROP TABLE SalesHistory;
GO
CREATE TABLE [dbo].[SalesHistory](
[SaleID] [int] NOT NULL,
[Product] [char](150) NULL,
[SaleDate] [datetime] NULL,
[SalePrice] [money] NULL
)
GO
ALTER TABLE SalesHistory
ADD CONSTRAINT uc_SaleID UNIQUE(SaleID)
GO
Check
This constraint limits the value
range, or domain, in a column. Check constraints check the acceptable values
against a logical expression defined in the constraint. These constraints are
similar to foreign key constraints in that they both govern the acceptable
values for a column or set of columns in a given row in a table. You can create
a check constraint at the column or table level. A check constraint on a single
column allows only certain values for those columns, while a table check
constraint can limit values in certain columns based on values in other fields
in the row.
The following script creates a check
constraint on the SalePrice column in the SalesHistory table, limiting entries
where the SalePrice must be greater than 4. Any attempt to enter a record with
the SalePrice present and less than 4 will result in an error.
IF OBJECT_ID('SalesHistory')>0
DROP TABLE SalesHistory;
GO
CREATE TABLE [dbo].[SalesHistory](
[SaleID] [int] NOT NULL,
[Product] [char](150) NULL,
[SaleDate] [datetime] NULL,
[SalePrice] [money] NULL CHECK (SalePrice > 4)
)
GO
Namespaces in asp.net?
Namespaces:
Ø Collection of Classes Is Called Namespace.
Ø
Namespaces are a way of grouping type names and reducing the
chance of name collisions.
Ø Namespace is logical division of class,
structure and interface OR way to organize your Visual Basic .NET code is through the use of
namespaces
Ø
The namespace with all the built-in functionality comes
under System namespace. All other namespaces comes under
this System namespace.
Namespace Declaration in C#
Ø using System;
Ø using System.Data;
Namespace Declaration in Vb
Ø
imports system;
Ø
imports system.Data;
Example:
namespace ExampleNamespace
{
class
TestExample
{
public
void ShowMessage()
{
Console.WriteLine("This is the TestExample namespace!");
}
}
}
1) The System.Web namespace
System.web namespace holds some basic ingredients which includes classes and built-in Objects like
System.web namespace holds some basic ingredients which includes classes and built-in Objects like
a.
Server
b.
Application
c.
Request
d.
Response
And Classes used for managing
a.
Cookies
b.
Configuring page caching
c.
Tracing Implementation
d.
Retrieving Information of Web Server and client browser
We uses built-in object
frequently .This namespace are very important for ASP.net application, it is
also required for User Interface , Web forms and Web services.
2) The System.Web.services namespace
The System.Web.services namespace is a initial point for creating the web services. It contains web service classes , which allow to create XML web services using Asp.Net . XML web services provides feature to exchange messages in loosely coupled environment. using protocol like SOAP , HTTP , XML .
Some classes are as follows
2) The System.Web.services namespace
The System.Web.services namespace is a initial point for creating the web services. It contains web service classes , which allow to create XML web services using Asp.Net . XML web services provides feature to exchange messages in loosely coupled environment. using protocol like SOAP , HTTP , XML .
Some classes are as follows
a.
WebMethodAttribute
b.
Webservice
c.
WebServiceAttribute
d.
WebServiceBindingAttribute
3) The System.web.UI.WebControls
namespace
The System.web.UI.WebControls namespace contains classes that provides to create web server controls on web pages. These controls run on the server so we can programmaticaly control elements . It also include form controls like text boxes and buttons. special purpose controls such as calender , and Data Grid . Web controls are more abstract than HTML controls . They also provide a shophisticated formatting properties and events . The System.web.UI.WebControls namespace contains web control class which is the base class for all web controls
Some classes are as follows
The System.web.UI.WebControls namespace contains classes that provides to create web server controls on web pages. These controls run on the server so we can programmaticaly control elements . It also include form controls like text boxes and buttons. special purpose controls such as calender , and Data Grid . Web controls are more abstract than HTML controls . They also provide a shophisticated formatting properties and events . The System.web.UI.WebControls namespace contains web control class which is the base class for all web controls
Some classes are as follows
a.
Calendar
b.
Check Box
c.
Button
d.
Base Data Bound Control
e.
Data Control Field etc
4) The System.web.UI namespace
The System.web.UI namespace includes classes that allows to create server controls with data- binding functionality , which has ability to save view state of given control and pages (.aspx pages) . Many of these types allows to support for controls System.web.UI .Html controls. It is a base class for all HTML ,Web, and User Controls. Every aspx pages comes under it. Control classes provides common set of functionslity
There are following controls available
The System.web.UI namespace includes classes that allows to create server controls with data- binding functionality , which has ability to save view state of given control and pages (.aspx pages) . Many of these types allows to support for controls System.web.UI .Html controls. It is a base class for all HTML ,Web, and User Controls. Every aspx pages comes under it. Control classes provides common set of functionslity
There are following controls available
- HTML
server controls
- Web
server controls
- User
controls
Some classes are as follows
a.
Attribute Collection
b.
BaseParser
c.
BaseTemplateParser
d.
AsyncPostBackTrigger etc
5) The System.web.sessionstate namespace
Session state management comes under The System.web.sessionstate namespace . That enable storage of data specific to a single client with in a web application on the server. Session state is ideal for sensitive data such as mailing address , credit card number , password , important numbers etc. Sesssion state can be used with clients that do not support cookies.
Some classes are as follows
Session state management comes under The System.web.sessionstate namespace . That enable storage of data specific to a single client with in a web application on the server. Session state is ideal for sensitive data such as mailing address , credit card number , password , important numbers etc. Sesssion state can be used with clients that do not support cookies.
Some classes are as follows
a.
HttpSessionState
b.
HttpSessionStateContainer
c.
SessionIDManager
d.
SessionStateModule etc
Insert Command with Examples?
> The INSERT INTO statement is used to insert new records in a
table.
> The SQL INSERT
statement is used
to insert a one or more records into a table.
Syntax:
INSERT
INTO table_name
VALUES (value1,value2,value3,...);
VALUES (value1,value2,value3,...);
And
INSERT INTO table_name (column1,column2,column3,...)
VALUES (value1,value2,value3,...);
VALUES (value1,value2,value3,...);
Alter command with examples?
Alter:
Ø
ALTER
TABLE statement to add a column, modify a column, drop a column, rename a
column or rename a table (with lots of clear, concise examples). We've also
added some practice exercises that you can try for yourself.
Ø
The SQL
ALTER TABLE command is used to modify the definition (structure) of a table by
modifying the definition of its columns. The ALTER command is used to perform
the following functions.
Syntax to add a column
ALTER TABLE table_name ADD column_name datatype;
For Example: To add a column "experience" to the
employee table, the query would be like
ALTER TABLE employee ADD experience number(3);
Syntax to drop a column
ALTER TABLE table_name DROP column_name;
For Example: To drop the column "location" from
the employee table, the query would be like
ALTER TABLE employee DROP location;
Syntax to modify a column
ALTER TABLE table_name MODIFY column_name datatype;
For Example: To modify the column salary in the employee
table, the query would be like
ALTER TABLE employee MODIFY salary number(15,2);