What are the differences between Iqueriable and IEnumerable?

Question

What are the differences between Iqueryable and IEnumerable?

Prasham Sabadra · Answer

Hi Please have a look at following links. http://www.c-sharpcorner.com/UploadFile/a20beb/ienumerable-vs-iqueryable-in-linq/ http://www.codeproject.com/Articles/732425/IEnumerable-Vs-IQueryable http://stackoverflow.com/questions/2433306/whats-the-difference-between-iqueryable-and-ienumerable

Ravi Patel · Answer

Hi  IEnumerable are found in a System.Collections Namespace while the IQueryable are found in a System.Linq Namespace. If you are use IEnumerable when querying data from in-memory collections like List Array collection etc And when querying data from out-memory (like remote database service) collections so you are use IQueryable. Because While querying data from database IEnumerable execute select query on server sideload data in-memory on client side and then filter data. Hence does more work and becomes slow. While querying data from database IQueryable execute select query on server side with all filters. Hence does less work and becomes fast. for more details check this link http://www.c-sharpcorner.com/UploadFile/a20beb/ienumerable-vs-iqueryable-in-linq/