Language-Integrated Query (LINQ) is a powerful feature in the .NET framework that enables us to query different data sources using a unified syntax. One of the critical benefits of LINQ is the ability to write dynamic queries.
Dynamic queries are queries that are constructed at runtime rather than at compile time. In other words, the query logic is not predefined; instead, it is generated based on user input or conditions at runtime.
To create dynamic queries in LINQ, we can use the "Queryable" class which provides a set of extension methods that allow us to construct queries dynamically. These extension methods can be used on any data source that implements the IQueryable interface, such as a database, an XML file, or an in-memory collection.
Some of the commonly used extension methods for dynamic queries in LINQ include:
To construct dynamic queries, we can chain multiple extension methods together. For example, to filter data based on a condition and then sort it by a specific property, we can use the following code:
var query = dbContext.Customers.Where(c => c.City == "London").OrderBy(c => c.LastName);
In the example above, the Where method is used to filter data where the city is London, and the OrderBy method is used to sort the filtered data by the last name of the customers.
Dynamic queries in LINQ provide a flexible and powerful way to query data sources at runtime. By using the extension methods provided by the "Queryable" class, we can construct complex queries that can handle various scenarios and conditions.
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