beauties | : yum : Fetch and display images | REST library

I get some errors from this SQL code. I am making a mock database for practice. I have looked at some work around and have redone the code a few times.

Everything has been created in order (I believe). Any help would be great! Am I referencing the incorrect tables/columns? Am I referencing different Data types that shouldn't be?

Here are the errors I get:

Msg 547, Level 16, State 0, Line 186
The INSERT statement conflicted with the FOREIGN KEY constraint "fk_bookid". The conflict occurred in database "db_City_Library", table "dbo.Books", column 'BookID'.

Msg 547, Level 16, State 0, Line 63
The ALTER TABLE statement conflicted with the FOREIGN KEY constraint "fk_publisher_name_books". The conflict occurred in database "db_City_Library", table "dbo.Publisher",

Code:

A peculiar error occurred today when was manipulating data in Postgres using database/sql and driver github.com/lib/pq. I have the following SQL schema created in Postgres:

These beauties come up from cloud functions. Not reproducible or traceable to a particular part of my code, and intermittent. My code updates a Google Sheets Spreadsheet whenever Firestore documents change. It uses Axios version 0.19.0

This is just an educational question, which could otherwise be avoided entirely by leveraging on tools such as range-v3.

Anyway, consider this example in which a variadic number of containers is passed to a function which returns a tuple of iterators:

I have 2 docker apps, both .NET Core, on Linux containers(Windows is a host), which need to talk: one, let's called it First, posting data to another one, let's call it Second. Both use kestrel. Under Docker I've created (using docker network command) a network, so those two apps could talk to each other.

I am using Visual Studio 2017 for debugging. I create console app to start communication. This app posting data to First docker app, which does some massaging and posts to Second docker app to get some love.

Up to the point of posting from First app to Second everything is going well, but during posting I see strange errors, which I could not decipher.

Here how I create WebHost instance for Second app, which receives posts:

ETA - Solution found. Nice work Stack Overflow beauties!! What would I do without you ;) ;)

I'm building a carousel, some items have images, others don't. I need to be able to target the items without images for styling, so I'm trying to add a class to the div that wraps the image if that makes sense?

What I have is this : For items with images: