Add primary keys and unique constraints to system catalogs

For those system catalogs that have a unique indexes, make a primary
key and unique constraint, using ALTER TABLE ... PRIMARY KEY/UNIQUE
USING INDEX.

This can be helpful for GUI tools that look for a primary key, and it
might in the future allow declaring foreign keys, for making schema
diagrams.

The constraint creation statements are automatically created by
genbki.pl from DECLARE_UNIQUE_INDEX directives.  To specify which one
of the available unique indexes is the primary key, use the new
directive DECLARE_UNIQUE_INDEX_PKEY instead.  By convention, we
usually make a catalog's OID column its primary key, if it has one.

Reviewed-by: Tom Lane <[email protected]>
Discussion: https://www.postgresql.org/message-id/flat/[email protected]

1 files changed, 8 insertions, 4 deletions

diff --git a/src/include/catalog/genbki.h b/src/include/catalog/genbki.h
index e26bde6d09b..5d05fafb5da 100644
--- a/src/include/catalog/genbki.h
+++ b/src/include/catalog/genbki.h
@@ -55,12 +55,15 @@
 #define DECLARE_TOAST(name,toastoid,indexoid) extern int no_such_variable
 
 /*
- * These lines processed by genbki.pl to create the statements
+ * These lines are processed by genbki.pl to create the statements
  * the bootstrap parser will turn into DefineIndex calls.
  *
- * The keyword is DECLARE_INDEX or DECLARE_UNIQUE_INDEX.  The first two
- * arguments are the index name and OID, the rest is much like a standard
- * 'create index' SQL command.
+ * The keyword is DECLARE_INDEX or DECLARE_UNIQUE_INDEX or
+ * DECLARE_UNIQUE_INDEX_PKEY.  ("PKEY" marks the index as being the catalog's
+ * primary key; currently this is only cosmetically different from a regular
+ * unique index.  By convention, we usually make a catalog's OID column its
+ * pkey, if it has one.)  The first two arguments are the index's name and
+ * OID, the rest is much like a standard 'create index' SQL command.
  *
  * For each index, we also provide a #define for its OID.  References to
  * the index in the C code should always use these #defines, not the actual
@@ -70,6 +73,7 @@
  */
 #define DECLARE_INDEX(name,oid,decl) extern int no_such_variable
 #define DECLARE_UNIQUE_INDEX(name,oid,decl) extern int no_such_variable
+#define DECLARE_UNIQUE_INDEX_PKEY(name,oid,decl) extern int no_such_variable
 
 /* The following are never defined; they are here only for documentation. */