Report duplicate property and label names with a proper error
Adding a property with the same name multiple times to a label on an
element, either within a single PROPERTIES clause or across statements
via ALTER PROPERTY GRAPH ... ADD PROPERTIES, previously failed with a
unique-index violation on pg_propgraph_label_property. The same class
of bug existed for labels: listing the same label multiple times on
one element in CREATE PROPERTY GRAPH, or adding a label to an element
that already has it via ALTER PROPERTY GRAPH ... ADD LABEL, failed
with a unique-index violation on pg_propgraph_element_label. Detect
the duplicates up front and raise a friendlier error in both cases.
For properties, the cross-statement duplicate is caught by a syscache
probe before insertion. The in-clause duplicate could have been
caught by the same probe if we issued a CommandCounterIncrement()
between property inserts, but that forces a catalog invalidation per
property purely to detect a condition we can check for free on the
in-memory target list. The list-based check is only needed when the
properties are listed explicitly; when they are derived from the
table's attributes, names are already unique.
For labels, a single syscache probe on pg_propgraph_element_label
suffices for both the in-clause and cross-statement cases because
insert_element_record() already issues CommandCounterIncrement()
between successive label inserts.
Author: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reported-by: Noah Misch <noah@leadboat.com>
Discussion: https://www.postgresql.org/message-id/flat/20260630173053.51.noahmisch%40microsoft.com
Branch
------
master
Details
-------
https://git.postgresql.org/pg/commitdiff/9b917a93116e6b8aac7ed837ded27696f7232505
Modified Files
--------------
src/backend/commands/propgraphcmds.c | 37 ++++++++++++++++++++--
.../regress/expected/create_property_graph.out | 14 ++++++++
src/test/regress/sql/create_property_graph.sql | 12 +++++++
3 files changed, 60 insertions(+), 3 deletions(-)
