I've been looking over the syntax for creating various database objects: tables, views, functions, etc., and I wondered why there seem to be some discrepancies.
For example, table creation syntax features [ IF NOT EXISTS ] but doesn't feature [ OR REPLACE ], function creation syntax is the inverse and has [ OR REPLACE ], but no [ IF NOT EXISTS ]. I also noticed that the syntax for creating VIEWS and creating MATERIALISED VIEWS is handled separately [1][2]. I was expecting to see one page of documentation with the syntax listed as something like: CREATE [ OR REPLACE ] [ MATERIALIZED ] VIEW [ IF NOT EXISTS ] view_name. Is this because a materialized view is actually a table and thus inherits the table creation syntax instead of the view creation syntax? How come table creation doesn't allow [ OR REPLACE ], and view creation doesn't allow [ IF NOT EXISTS ]? Is this just how the SQL spec defines things? Thanks, Aidan. [1] https://www.postgresql.org/docs/current/sql-createview.html [2] https://www.postgresql.org/docs/current/sql-creatematerializedview.html
