LINQ Queries

LINQ queries demonstrate how to operate and query the CSV objects wrapped in an Entity Framework data model. Below are some examples of LINQ queries supported by the Entity framework.

Contains

Retrieve all records from the Books table that contain "Agriculture" in their Industry name.

var histories = from p in context.Books
                where p.Industry_name.Contains("Agriculture") //using Contains to display Industry names that contain "Agriculture"
                select p;

Count

Count all entities that match a given criterion.

var _count = (from p in db.SampleCSV
             select p).Count(); //Count Query based on the number of records selected

Select and Filter

Select records from the table SampleCSV that belong to the Year equal to 2011.

var histories = from p in db.SampleCSV
               where p.Year== 2011
               select p;

Limit

Select the first 2 records.

var histories = (from p in db.SampleCSV
                select p).Take(2); //taking 2 records

Order By

Sort records form the table SampleCSV by the Year in descending order.

var histories = (from p in db.SampleCSV
                orderby p.Year descending //Implementing Order By
                select p).Take(2); //taking 2 records

Group By

Group records from the SampleCsvs table based on the Age property. The groups are then ordered in descending order based on the Age.

var sampleTable = context.SampleCsvs.AsEnumerable();
var querySample = from b in sampleTable
                  group b by b.Age into newGroup
                  orderby newGroup.Key descending
                  select newGroup;