On 02/12/2024 03:15, Tom Lane wrote:
Michael Paquier <mich...@paquier.xyz> writes:
If I'm parsing the spec right, the doc mentions in its 5)~6) of the
syntax rules in CREATE SCHEMA that non-schema-qualified objects should
use the new schema name defined in the CREATE SCHEMA query. So that
pretty much settles the rules to use when having a new object that has
a reference to a non-qualified object created in the same CREATE
SCHEMA query?
I don't see where you're getting that from? DB2 says that unqualified
reference names (not to be confused with unqualified creation-target
names) are taken to be in the new schema, but I don't see any
corresponding restriction in the spec.
What I do see (11.1 SR 6 in SQL:2021) is:
If <schema path specification> is not specified, then a <schema
path specification> containing an implementation-defined <schema
name list> that contains the <schema name> contained in <schema
name clause> is implicit.
What I read this as is that the "search path" during schema-element
creation must include at least the new schema, but can also include
some other schemas as defined by the implementation. That makes
our behavior compliant, because we can define the other schemas
as those in the session's prevailing search_path. (DB2's behavior
is also compliant, but they're defining the path as containing only
the new schema.)
Also, if SQL intended to constrain the search path for unqualified
identifiers to be only the new schema, they'd hardly need a concept
of <schema path specification> at all.
I looked up the original paper (MUN-051) that introduced the <schema
path specification> and it says, "The paper is proposing the use of
paths only to resolve unqualified routine invocations."
That doesn't seem to have been explained much by the rest of the spec,
but it is visible in the definition of <path specification> which says,
"Specify an order for searching for an SQL-invoked routine."
I can find nowhere that says that the path can or cannot be used for
other objects.
--
Vik Fearing
