Translating a Complex SQL Query into LINQ

Data and Databases
1

I’m still getting acquainted with LINQ and have run into a SQL query I now need to convert. I’m testing my solution in a local LINQ development tool, but I’m not entirely sure how to mimic the original logic. Below is an alternative SQL example that shows what I’m trying to achieve:

SELECT jRecord.*, 
       (SELECT TOP 1 1 FROM AppRecords AS rec WHERE rec.JobRef = jRecord.JobID AND rec.UserRef = @currentUser) AS HasApplied
FROM JobListings AS jRecord;

Any pointers on correctly restructuring this into LINQ would be very helpful.

2

hey, try uing a join then use firstOrDefualt to flag recs. u can also check for null to indicate applied state, maybe using inline let bindings. hope it helps, been there with this linq junk!

3

hey, im tinkering with similar linq stuff. ive had some luck nestin subqueries with an anonymous type. did u play around with group join? what exactly r u strugglin with?

4

In my experience, using the Any() method simplifies the translation of this SQL query into LINQ. Instead of formulating a join or relying on subqueries for each record, I find that selecting an anonymous object that includes all job listing fields and a flag based on recs.Any(rec => rec.JobRef == jRecord.JobID && rec.UserRef == currentUser) results in code that is both clear and efficient. This approach not only closely mimics the logic of the original SQL but also enhances readability and maintainability within the LINQ query.