ERROR: Msg 8120, Level 16, State 1, Line 27

Column 'Documents.document_id' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY...

This myth goes back to the very early days of DB2. It was IBM's superstition for pretty much the same reason you gave. The truth is maintaining the views is...

Please follow forum netiquette and post DDL. I presume that your boss does not make you try to program from graphics and pretty pictures. I also hope you know the...

Why did you allow all those columns to be NULL-able? You can't default them to an empty string or blank or some other symbol instead in your DDL? And why...

You're getting there! You still have some basic fundamental flaws in your DDL. In a properly designed RDBMS, the data element names will follow the ISO 11179 naming rules. This...

Please look up these two articles for help.

https://www.red-gate.com/simple-talk/sql/learn-sql-server/values-and-long-parameter-lists-part-i/

https://www.red-gate.com/simple-talk/sql/learn-sql-server/values-and-long-parameter-lists-part-ii/

By definition, a table must have a key. You don't have one in your DDL so you need to fix that. You have some misconceptions about RDBMS that you might...

I wish you would post an actual table. This DDL is not a valid table because it lacks a key. The fact that you named your table "employee" says that...

There are no such creatures as a generic "date", generic "id", or generic "status"; I also seriously doubt that the status is ever 150 characters of Chinese. You define something...

>> Example (dates changed to integers to simplify the problem): <<

Don't do this. We were very proud of putting temporal data types into the language. Unfortunately, what you posted for...

>> Create a table to track the last used child_id [sic] per parent_id [sic] <<

The terms "child" and "parent" come from the old pointer chain/hierarchical databases. The correct terms in...

Actually, I found you do need to yell at people a little bit especially when they are screwing up. By definition, a "minimal example" would include a key because that's...

That's a really bad idea. Identity is proprietary profit that numbers the insertions to a table in the old Sybase family of early relational databases. It is by definition, not...

The first thing I want to do is correct your DDL. You don't seem to know the table must have a key. This is not an option; it is a...

There's a pattern for this for you don't have to do this weird nonrelational numbering. Entities that exist by themselves are called "strong"; entities that depend on a strong entity...