pgsql: Readable identity strings for property graph objects

Readable identity strings for property graph objects

The "identity" column of pg_identify_object() for property graph
objects can be long string of names connected by "of", e.g. "a of l of
e of g". The type of the first named object is given by column
"type". But the types of intermediate objects are not easy to find
from the identity string especially when some of them share the same
name. Some objects, like user mappings or authorization identifier
members, add types of objects other than the first one in the identity
string. Do the same for property graph objects.

Author: Ashutosh Bapat <ashutosh(dot)bapat(dot)oss(at)gmail(dot)com>
Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>
Discussion: https://www.postgresql.org/message-id/flat/aej1DkLwhyZWmtxJ%40bdtpg

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2a7e95b659df2903420e27542e9127c50e8f2a17

Modified Files
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src/backend/catalog/objectaddress.c | 10 ++---
.../regress/expected/create_property_graph.out | 50 +++++++++++-----------
2 files changed, 30 insertions(+), 30 deletions(-)