The reason for the error is that transformOnConflictArbiter applies RelationIsUsedAsCatalogTable() to something that it doesn't know to be a plain relation --- it's a view in this case. And that macro blindly assumes that relation->rd_options is a StdRdOptions struct, when in this case it's actually a ViewOptions struct.
Now that I've seen this I wonder which other uses of rd_options are potentially broken. RelationIsUsedAsCatalogTable() is hardly the only macro that is assuming with little justification that it's applied to the right kind of reloptions.
Right, there are many macros, which blindly assume the rd_options
to be of specific type. Here is the list of such macros :
RelationGetFillFactor
RelationIsUsedAsCatalogTable
RelationGetParallelWorkers
RelationIsSecurityView
RelationHasCheckOption
RelationHasLocalCheckOption
RelationHasCascadedCheckOption
BrinGetPagesPerRange
GinGetUseFastUpdate
GinGetPendingListCleanupSize
For the macros associated with specific index type, it might be alright to
assume the type of the rd_options because those have very limited usage.
However for the rest of the macros, the code does not limit its usage. This can
lead to problems as you described above .
We could band-aid this by having the RelationIsUsedAsCatalogTable() macro check relation->relkind, but I'm inclined to think that the right fix going forward is to insist that StdRdOptions, ViewOptions, and the other in-memory representations of reloptions ought to be self-identifying somehow. We could add a field to them similar to nodeTag, but one of the things that was envisioned to begin with is relation types that have StdRdOptions as the first part of a larger struct. I'm not sure how to make that work with a tag.
Thoughts?
Yes, it seems appropriate to tag all types of the rd_options with an
identification and maybe check for that identification within each macro.
Currently, there are following types of rd_options as far as I could find:
GiSTOptions
BrinOptions
GinOptions
StdRdOptions
ViewOptions
BloomOptions (from contrib)
I am not clear on how the identification field in the above structures can
be a problem, for the relations have StdRdOptions as the first part of a
