Notes for learning from Linq

Notes for learning from Linq

When writing a Linq query in the background, the system will give a warning for the query statement we write: possible multiple enumeration of ienumerable.

The cause of this warning is:

If the query is a database query, the query statement will be executed twice or more times from the database. We can optimize the query. The optimization method is

When this query is first executed from the database, it is converted to a local List. In future queries, this List will be directly used for query and will not be executed from the database.