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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. |
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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. |
| C# |
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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. |
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var histories = from p in db.SampleCSV
where p.Year== 2011
select p; | |
| Limit
Select the first 2 records. |
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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. |
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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. |
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var sampleTable = context.SampleCsvs.AsEnumerable();
var querySample = from b in sampleTable
group b by b.Age into newGroup
orderby newGroup.Key descending
select newGroup; | |
