I'm not using oracle - I'm using MySQL. However, I created the table creation SQL script myself since I wanted to normalize the database somewhat, and needed to make some changes (timestamp fields need to be datestamp, etc). Now I only update the structure when there are changes in the release notes. Hope that helps.
When we implemented Canvas Data in Oracle, I came across a DDL script online for MySql. It required some tweaking to deal with Oracle-specific limitations (table name and column name lengths) as well as some data type changes (longtext-->clob) but that script was a lifesaver. I wish I still had that link. But check out canvancement/canvas-data/mysql at master · jamesjonesmath/canvancement · GitHub for some php code that will generate the MySql DDL from schema.json. I haven't checked it to see if it's using the current schema.json but it should get you started in the right direction.
I haven't updated the MySQL script to the latest version yet, but the PHP code is designed to generate a MySQL version by fetching the latest version of the schema. The PHP code is up a directory from the link you gave, which is to the MySQL code.