Custom reloptions for table AM

Let table AM define custom reloptions for its tables. This allows specifying
AM-specific parameters by the WITH clause when creating a table.

The reloptions, which could be used outside of table AM, are now extracted
into the CommonRdOptions data structure.  These options could be by decision
of table AM directly specified by a user or calculated in some way.

The new test module test_tam_options evaluates the ability to set up custom
reloptions and calculate fields of CommonRdOptions on their base.

The code may use some parts from prior work by Hao Wu.

Discussion: https://postgr.es/m/CAPpHfdurb9ycV8udYqM%3Do0sPS66PJ4RCBM1g-bBpvzUfogY0EA%40mail.gmail.com
Discussion: https://postgr.es/m/AMUA1wBBBxfc3tKRLLdU64rb.1.1683276279979.Hmail.wuhao%40hashdata.cn
Reviewed-by: Reviewed-by: Pavel Borisov, Matthias van de Meent, Jess Davis

1 files changed, 7 insertions, 5 deletions

diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index c367ede6f88..7cb79ebcedd 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -2674,19 +2674,21 @@ static AutoVacOpts *
 extract_autovac_opts(HeapTuple tup, TupleDesc pg_class_desc)
 {
 	bytea	   *relopts;
+	CommonRdOptions common;
 	AutoVacOpts *av;
 
 	Assert(((Form_pg_class) GETSTRUCT(tup))->relkind == RELKIND_RELATION ||
 		   ((Form_pg_class) GETSTRUCT(tup))->relkind == RELKIND_MATVIEW ||
 		   ((Form_pg_class) GETSTRUCT(tup))->relkind == RELKIND_TOASTVALUE);
 
-	relopts = extractRelOptions(tup, pg_class_desc, NULL);
-	if (relopts == NULL)
-		return NULL;
+	relopts = extractRelOptions(tup, pg_class_desc,
+								GetTableAmRoutineByAmOid(((Form_pg_class) GETSTRUCT(tup))->relam),
+								NULL, &common);
+	if (relopts)
+		pfree(relopts);
 
 	av = palloc(sizeof(AutoVacOpts));
-	memcpy(av, &(((StdRdOptions *) relopts)->autovacuum), sizeof(AutoVacOpts));
-	pfree(relopts);
+	memcpy(av, &(common.autovacuum), sizeof(AutoVacOpts));
 
 	return av;
 }