Hi Kevin

"... SELECT MAX( <pk_column_name> ) + 1 ..."

*Never* do it this way. It is worst praxis ever to get garantied PK values.

Even when you have done it befor - it does'nt make that better.

Use a Sequence and trigger (or a table API) or if you are on12c  AUTO_INCREMENT -> https://docs.oracle.com/cd/E17952_01/mysql-5.5-en/example-auto-increment.html)

I have to apologize, here an adjustment:

The link above  points to the MySQL documentations.

The syntax for the autoincrement feature in oracle DB (=Identity column) is different:

https://docs.oracle.com/database/121/SQLRF/statements_7002.htm#CJAHCAFF

Thank you Sven for pointing out my mistake!

ROWID is a completly diferent story.

It looks good at the first glance; and surely there are situations where it make sense using it. However it is NOT a valid substitution for a PK that every table should have.

Regards

Andre

Apex in some scenarios relies on best practices.

It is best practice to have a primary key that is populated "automagically" by the database.

Usually by a sequence generator + database trigger to put the generated values into the PK column.

Apex then is able to fetch this value useing the return clause during an insert statement.

IGs can do this too. But they have some more options. However the final insert is only done when the submit button was pressed and all the validations went through.

So there shouldn't be a validation that requires a NOT NULL value in the PK column.

If you create a table using Apex SQL workshop, then you have an option that exactly this best practice is used to generate your IDs.

Also make sure your column information is correctly set: