1. Difference between First vs
FirstOrDefault in LINQ
- First: Gives
first record from the collection, if collection doesn't have any object
then throws error.
- FirstOrDefault:
FirstOrDefault extension method is used to retrieve the first element from
the collection, if not then gives null.
2. Difference between Last vs
LastOrDefault in LINQ?
- Last:Last extension method
gives last element from the collection. If there is no element in the
collection, it throws error.
- LastOrDefault:LastOrDefault
extension method gives the last element form the collection, if not gives
null.
3.
When will we use ThenBy in LINQ?
ThenBy is used
with OrderBy or OrderByDescending. It is used to apply sorting on already
sorted collection using OrderBy or OrderByDescending.
4.
Where to Use SequenceEqual ?
SequenceEqual extension method is used to determine if both collections
sequence are equal.
5.
what is mean by SkipWhile?
SkipWhile extension method is
used to skip the elements that satisfies the given filter criteria till it
doens't get any element that doesn't satisfy.
6.
How to use Take Method in LINQ?
Take extension method is used to take
specified number of elements from the collection.
7.
What is mean by Lambda expression?
- A lambda expression is an
function that contain many expressions and statements.
- Lambda expression used to
create delegates or expression tree types.
- All lambda expressions use
the lambda operator =>, which is read as "goes to".
- The left side of the lambda
operator specifies the input parameters.
- The right side holds the
expression or statement block.
8.
What is ORM?
ORM stands for Object-Relational
Mapping. Sometimes it is called O/RM, or O/R mapping. It is a programming
technique that contains a set of classes that map relational database entities
to objects in a specific programming language.
9.
What is ODBC?
ODBC (Open Database Connectivity) was
developed to unify all of the communication protocols for various RDBMSs. ODBC
was designed to be independent of programming languages, database systems, and
Operating Systems. So with ODBC, an application could communicate with
different RDBMSs by using the same code, simply by replacing the underlying
ODBC drivers.
10. What is LINQ To SQL?
- LINQ to SQL is a
component of the .NET Framework version 3.5 that provides a run-time
infrastructure for managing relational data as objects.
- LINQ to SQL fully supports
transactions, views, Stored Procedures, and user-defined functions. It
also provides an easy way to integrate data validation and business logic
rules into your data model, and supports single table inheritance in the
object model.
- LINQ to SQL, ADO.NET
SqlClient adapters are used to communicate with real SQL Server databases.
11. Difference between
LINQ To SQL and LINQ To Object?
·
LINQ to SQL needs a Data Context object. The Data Context object is the
bridge between LINQ and the database. LINQ to Objects doesn’t need any
intermediate LINQ provider or API.
·
LINQ to SQL returns data of type IQueryable<T> while LINQ to
Objects returns data of type IEnumerable<T>.
·
LINQ to SQL is translated to SQL by way of Expression Trees, which allow
them to be evaluated as a single unit and translated to the appropriate and
optimal SQL statements. LINQ to Objects does not need to be translated.
·
LINQ to SQL is translated to SQL calls and executed on the specified
database while LINQ to Objects is executed in the local machine memory.
12. What is mean by
Entity Framework?
·
ADO.NET Entity Framework (EF) was first released with Visual Studio 2008
and .NET Framework 3.5 Service Pack 1. So far, many people view EF as just
another ORM product from Microsoft, though by design it is supposed to be much
more powerful than just an ORM tool.
·
The conceptual data model schema is expressed in the Conceptual Schema
Definition Language (CSDL), the actual storage model is expressed in the
Storage Schema Definition Language (SSDL), and the mapping in between is
expressed in the Mapping Schema Language (MSL).
13. Difference between
LINQ To SQL and LINQ To Entities?
·
LINQ to Entities applications work against a conceptual data model
(EDM). All mappings between the languages and the databases go through the new
EntityClient mapping provider. The application no longer connects directly to a
database or sees any database-specific construct; the entire application
operates in terms of the higher-level EDM model.
14. What are all the
Operator Type in LINQ To Object?
·
Aggregation Aggregate, Average, Count, LongCount, Max, Min, Sum
·
Conversion Cast, OfType, ToArray, ToDictionary, ToList, ToLookup,
ToSequence
·
Element DefaultIfEmpty, ElementAt, ElementAtOrDefault, First, FirstOrDefault,
Last, LastOrDefault, Single, SingleOrDefault
·
Equality EqualAll
·
Generation Empty, Range, Repeat
·
Grouping GroupBy
·
Joining GroupJoin, Join
·
Ordering OrderBy, ThenBy, OrderByDescending, ThenByDescending, Reverse
·
Partitioning Skip, SkipWhile, Take, TakeWhile
·
Quantifiers All, Any, Contains
·
Restriction Where
·
Selection Select, SelectMany
·
Set Concat, Distinct, Except, Intersect, Union