Language Integrated Query (LINQ) Interview Questions and Answers

1 :: What is Quantifiers in reference linq to Dataset?

Quantifier Operators return the Boolean value (either True or false) if some or all the elements in a sequence satisfy a condition,
Mainly two Quantifiers in linq:

Any
All

Examples (vb)

"Any" to determine if any of the words in the array contain the substring

Public Sub ExampleAny()
Dim words() = {"believe", "relief", "receipt", "field"}
Dim iAfterE = words.Any(Function(w) w.Contains("ei"))
Console.WriteLine("There is a word that contains in the
list that contains 'ei': {0}", iAfterE)
End Sub


Result:
There is a word that contains in the list that contains 'ei': True

"All" to return a grouped a list of products only for categories that have all of their products in stock

Public Sub Quantifier_All_Exam()
Dim products = GetProductList()
Dim productGroups = From p In products _
Group p By p.Category Into Group _
Where (Group.All(Function(p) p.UnitsInStock > 0)) _
Select Category, ProductGroup = Group
ObjectDumper.Write(productGroups, 1)
End Sub

0/5 Rating (0 vote)

Is This Answer Correct?    1 Yes 0 No

2 :: Why do we use “Contains” method for strings type functions?

Contains method Used to find all matching records From Given string using Matching keywords.
Example-
This Examples returns the Customer Names from Customer tables whose Names have contains “Anders”

Public void LinqToSqlStringUsingContains()
{
Var q = From c In db.Customers _
Where c.ContactName.Contains("Anders") _
Select c
ObjectDumper.Write(q)
}

0/5 Rating (0 vote)

Is This Answer Correct?    0 Yes 1 No

3 :: List out the Data Context Functions. Where do we use “SubmitChanges()”?

Create Database ()
Delete database ()
Database Exist ()
Submit Changes ()
Create Query()
Log()
SubmitChanges() - SunbmitChanges Data Context Fuction Used to submit any update to the actual database.

0/5 Rating (0 vote)

Is This Answer Correct?    1 Yes 0 No

4 :: Differentiate between Conversion Operator “IEnumerable” and “ToDictionary” of LINQ?

IEnumerable and To Dictionary both are Conversion Operator which are used to solved to conversion type Problems.
“AsEnumerable ” operator simply returns the source sequence as an object of type IEnumerable. This kind of “conversion on the fly” makes it possible to call the general-purpose extension methods over source, even if its type has specific implementations of them
Signature:

public static IEnumerable<T> AsEnumerable<T>
(
this IEnumerable<T> source
);


“ToDictionary ” Conversion Operator is the instance of Dictionary (k,T) . The “keySelector ”predicate identifies the key of each item while “elementSelector ”, if provided, is used to extract each single item.
Key and elementSelector Predicate can be Used in following ways-
Example-

Public void ToDictionatyExample()
{
Var scoreRecords=
{
new {Name = "Alice",Score = 50 },
new {Name = "Bob",Score = 40 },
new {Name = "Cathy", Score = 45}
};
Var scoreRecordsDict = scoreRecords.ToDictionary(sr => sr.Name);
Console.WriteLine("Bob's score: {0}", scoreRecordsDict("Bob"));
}


Result: Bob's score: { Name = Bob, Score = 40 }

0/5 Rating (0 vote)

Is This Answer Correct?    1 Yes 0 No

5 :: How can we find Sequence of Items in two different array (same Type) in the same order using linq query?

Public void MatchSequenceLinq()
{
Var wordsA = {"Rahul","ashok","sweta"};
Var wordsB = {"rahul","ashok","sweta"};
var match = wordsA.SequenceEqual(wordsB);
Console.WriteLine("The sequences match: {0}", match);
}

0/5 Rating (0 vote)

Is This Answer Correct?    1 Yes 0 No