Don't require pg_class.dat to contain correct relnatts values.

Practically everybody who's ever added a column to one of the bootstrap
catalogs has been burnt by the need to update the relnatts field in the
initial pg_class data to match.  Now that we use Perl scripts to
generate postgres.bki, we can have the machines take care of that,
by filling the field during genbki.pl.

While at it, use the BKI_DEFAULTS mechanism to eliminate repetitive
specifications of other column values in pg_class.dat, too.  They
weren't particularly a maintenance problem, but this way is prettier
(certainly the spotty previous usage of BKI_DEFAULTS wasn't pretty).

No catversion bump needed, since this doesn't actually change the
contents of postgres.bki.

Per gripe from Justin Pryzby, though this is quite different from
his originally proposed solution.

Amit Langote, John Naylor, Tom Lane

Discussion: https://postgr.es/m/20200212182337.GZ1412@telsasoft.com

diff --git a/src/backend/catalog/genbki.pl b/src/backend/catalog/genbki.pl
index 803251207b03a1844e1626e5d459a0f6981154d6..ad24f4dcb93aba172210a67abe51728bbc0f6339 100644 (file)
--- a/src/backend/catalog/genbki.pl
+++ b/src/backend/catalog/genbki.pl
@@ -184,6 +184,15 @@ my $PG_CATALOG_NAMESPACE =
    'PG_CATALOG_NAMESPACE');
 
 
+# Fill in pg_class.relnatts by looking at the referenced catalog's schema.
+# This is ugly but there's no better place; Catalog::AddDefaultValues
+# can't do it, for lack of easy access to the other catalog.
+foreach my $row (@{ $catalog_data{pg_class} })
+{
+   $row->{relnatts} = scalar(@{ $catalogs{ $row->{relname} }->{columns} });
+}
+
+
 # Build lookup tables.
 
 # access method OID lookup

diff --git a/src/include/catalog/pg_class.dat b/src/include/catalog/pg_class.dat
index f70d5bacb988f7e4e3ce51da24fde374d2b55cc8..b28bba7cc3f7ecab4986e774141a107b787cac01 100644 (file)
--- a/src/include/catalog/pg_class.dat
+++ b/src/include/catalog/pg_class.dat
@@ -14,51 +14,15 @@
 
 # Note: only bootstrap catalogs, ie those marked BKI_BOOTSTRAP, need to
 # have entries here.  Be sure that the OIDs listed here match those given in
-# their CATALOG and BKI_ROWTYPE_OID macros, and that the relnatts values are
-# correct.
-
-# Note: "3" in the relfrozenxid column stands for FirstNormalTransactionId;
-# similarly, "1" in relminmxid stands for FirstMultiXactId
+# their CATALOG and BKI_ROWTYPE_OID macros.
 
 { oid => '1247',
-  relname => 'pg_type', reltype => 'pg_type', relam => 'heap',
-  relfilenode => '0', relpages => '0', reltuples => '0', relallvisible => '0',
-  reltoastrelid => '0', relhasindex => 'f', relisshared => 'f',
-  relpersistence => 'p', relkind => 'r', relnatts => '31', relchecks => '0',
-  relhasrules => 'f', relhastriggers => 'f', relhassubclass => 'f',
-  relrowsecurity => 'f', relforcerowsecurity => 'f', relispopulated => 't',
-  relreplident => 'n', relispartition => 'f', relfrozenxid => '3',
-  relminmxid => '1', relacl => '_null_', reloptions => '_null_',
-  relpartbound => '_null_' },
+  relname => 'pg_type', reltype => 'pg_type' },
 { oid => '1249',
-  relname => 'pg_attribute', reltype => 'pg_attribute', relam => 'heap',
-  relfilenode => '0', relpages => '0', reltuples => '0', relallvisible => '0',
-  reltoastrelid => '0', relhasindex => 'f', relisshared => 'f',
-  relpersistence => 'p', relkind => 'r', relnatts => '25', relchecks => '0',
-  relhasrules => 'f', relhastriggers => 'f', relhassubclass => 'f',
-  relrowsecurity => 'f', relforcerowsecurity => 'f', relispopulated => 't',
-  relreplident => 'n', relispartition => 'f', relfrozenxid => '3',
-  relminmxid => '1', relacl => '_null_', reloptions => '_null_',
-  relpartbound => '_null_' },
+  relname => 'pg_attribute', reltype => 'pg_attribute' },
 { oid => '1255',
-  relname => 'pg_proc', reltype => 'pg_proc', relam => 'heap',
-  relfilenode => '0', relpages => '0', reltuples => '0', relallvisible => '0',
-  reltoastrelid => '0', relhasindex => 'f', relisshared => 'f',
-  relpersistence => 'p', relkind => 'r', relnatts => '29', relchecks => '0',
-  relhasrules => 'f', relhastriggers => 'f', relhassubclass => 'f',
-  relrowsecurity => 'f', relforcerowsecurity => 'f', relispopulated => 't',
-  relreplident => 'n', relispartition => 'f', relfrozenxid => '3',
-  relminmxid => '1', relacl => '_null_', reloptions => '_null_',
-  relpartbound => '_null_' },
+  relname => 'pg_proc', reltype => 'pg_proc' },
 { oid => '1259',
-  relname => 'pg_class', reltype => 'pg_class', relam => 'heap',
-  relfilenode => '0', relpages => '0', reltuples => '0', relallvisible => '0',
-  reltoastrelid => '0', relhasindex => 'f', relisshared => 'f',
-  relpersistence => 'p', relkind => 'r', relnatts => '33', relchecks => '0',
-  relhasrules => 'f', relhastriggers => 'f', relhassubclass => 'f',
-  relrowsecurity => 'f', relforcerowsecurity => 'f', relispopulated => 't',
-  relreplident => 'n', relispartition => 'f', relfrozenxid => '3',
-  relminmxid => '1', relacl => '_null_', reloptions => '_null_',
-  relpartbound => '_null_' },
+  relname => 'pg_class', reltype => 'pg_class' },
 
 ]

diff --git a/src/include/catalog/pg_class.h b/src/include/catalog/pg_class.h
index a12fc1fc46251d5ea9709a819b5d6ddd9fc306ae..78b33b2a7f9b8ae9b0e7b304b86ae738e04f3d5f 100644 (file)
--- a/src/include/catalog/pg_class.h
+++ b/src/include/catalog/pg_class.h
@@ -24,6 +24,9 @@
 /* ----------------
  *     pg_class definition.  cpp turns this into
  *     typedef struct FormData_pg_class
+ *
+ * Note that the BKI_DEFAULT values below are only used for rows describing
+ * BKI_BOOTSTRAP catalogs, since only those rows appear in pg_class.dat.
  * ----------------
  */
 CATALOG(pg_class,1259,RelationRelationId) BKI_BOOTSTRAP BKI_ROWTYPE_OID(83,RelationRelation_Rowtype_Id) BKI_SCHEMA_MACRO
@@ -47,41 +50,41 @@ CATALOG(pg_class,1259,RelationRelationId) BKI_BOOTSTRAP BKI_ROWTYPE_OID(83,Relat
    Oid         relowner BKI_DEFAULT(PGUID);
 
    /* access method; 0 if not a table / index */
-   Oid         relam BKI_LOOKUP(pg_am);
+   Oid         relam BKI_DEFAULT(heap) BKI_LOOKUP(pg_am);
 
    /* identifier of physical storage file */
    /* relfilenode == 0 means it is a "mapped" relation, see relmapper.c */
-   Oid         relfilenode;
+   Oid         relfilenode BKI_DEFAULT(0);
 
    /* identifier of table space for relation (0 means default for database) */
    Oid         reltablespace BKI_DEFAULT(0) BKI_LOOKUP(pg_tablespace);
 
    /* # of blocks (not always up-to-date) */
-   int32       relpages;
+   int32       relpages BKI_DEFAULT(0);
 
    /* # of tuples (not always up-to-date) */
-   float4      reltuples;
+   float4      reltuples BKI_DEFAULT(0);
 
    /* # of all-visible blocks (not always up-to-date) */
-   int32       relallvisible;
+   int32       relallvisible BKI_DEFAULT(0);
 
    /* OID of toast table; 0 if none */
-   Oid         reltoastrelid;
+   Oid         reltoastrelid BKI_DEFAULT(0);
 
    /* T if has (or has had) any indexes */
-   bool        relhasindex;
+   bool        relhasindex BKI_DEFAULT(f);
 
    /* T if shared across databases */
-   bool        relisshared;
+   bool        relisshared BKI_DEFAULT(f);
 
    /* see RELPERSISTENCE_xxx constants below */
-   char        relpersistence;
+   char        relpersistence BKI_DEFAULT(p);
 
    /* see RELKIND_xxx constants below */
-   char        relkind;
+   char        relkind BKI_DEFAULT(r);
 
    /* number of user attributes */
-   int16       relnatts;
+   int16       relnatts BKI_DEFAULT(0);    /* genbki.pl will fill this in */
 
    /*
     * Class pg_attribute must contain exactly "relnatts" user attributes
@@ -90,51 +93,51 @@ CATALOG(pg_class,1259,RelationRelationId) BKI_BOOTSTRAP BKI_ROWTYPE_OID(83,Relat
     */
 
    /* # of CHECK constraints for class */
-   int16       relchecks;
+   int16       relchecks BKI_DEFAULT(0);
 
    /* has (or has had) any rules */
-   bool        relhasrules;
+   bool        relhasrules BKI_DEFAULT(f);
 
    /* has (or has had) any TRIGGERs */
-   bool        relhastriggers;
+   bool        relhastriggers BKI_DEFAULT(f);
 
    /* has (or has had) child tables or indexes */
-   bool        relhassubclass;
+   bool        relhassubclass BKI_DEFAULT(f);
 
    /* row security is enabled or not */
-   bool        relrowsecurity;
+   bool        relrowsecurity BKI_DEFAULT(f);
 
    /* row security forced for owners or not */
-   bool        relforcerowsecurity;
+   bool        relforcerowsecurity BKI_DEFAULT(f);
 
    /* matview currently holds query results */
-   bool        relispopulated;
+   bool        relispopulated BKI_DEFAULT(t);
 
    /* see REPLICA_IDENTITY_xxx constants */
-   char        relreplident;
+   char        relreplident BKI_DEFAULT(n);
 
    /* is relation a partition? */
-   bool        relispartition;
+   bool        relispartition BKI_DEFAULT(f);
 
    /* heap for rewrite during DDL, link to original rel */
    Oid         relrewrite BKI_DEFAULT(0);
 
    /* all Xids < this are frozen in this rel */
-   TransactionId relfrozenxid;
+   TransactionId relfrozenxid BKI_DEFAULT(3);  /* FirstNormalTransactionId */
 
    /* all multixacts in this rel are >= this; it is really a MultiXactId */
-   TransactionId relminmxid;
+   TransactionId relminmxid BKI_DEFAULT(1);    /* FirstMultiXactId */
 
 #ifdef CATALOG_VARLEN          /* variable-length fields start here */
    /* NOTE: These fields are not present in a relcache entry's rd_rel field. */
    /* access permissions */
-   aclitem     relacl[1];
+   aclitem     relacl[1] BKI_DEFAULT(_null_);
 
    /* access-method-specific options */
-   text        reloptions[1];
+   text        reloptions[1] BKI_DEFAULT(_null_);
 
    /* partition bound node tree */
-   pg_node_tree relpartbound;
+   pg_node_tree relpartbound BKI_DEFAULT(_null_);
 #endif
 } FormData_pg_class;