Make it possible to execute crashed CREATE/DROP commands again.

Now indexes of pg_class and pg_type are unique indexes
and guarantee the uniqueness of correponding attributes.
heap_create() was changed to take another boolean parameter
which allows to postpone the creation of disk file.
The name of rd_nonameunlinked was changed to rd_unlinked.
It is used generally(not only for noname relations) now.
Requires initdb.

src/backend/bootstrap/bootparse.y

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootparse.y,v 1.27 1999/07/17 20:16:46 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootparse.y,v 1.28 1999/11/04 08:00:58 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -80,7 +80,7 @@ static Oid objectid;
 %token <ival> CONST ID
 %token OPEN XCLOSE XCREATE INSERT_TUPLE
 %token STRING XDEFINE
-%token XDECLARE INDEX ON USING XBUILD INDICES
+%token XDECLARE INDEX ON USING XBUILD INDICES UNIQUE
 %token COMMA EQUALS LPAREN RPAREN
 %token OBJ_ID XBOOTSTRAP NULLVAL
 %start TopLevel
@@ -106,6 +106,7 @@ Boot_Query :
 		| Boot_CreateStmt
 		| Boot_InsertStmt
 		| Boot_DeclareIndexStmt
+		| Boot_DeclareUniqueIndexStmt
 		| Boot_BuildIndsStmt
 		;
 
@@ -164,7 +165,7 @@ Boot_CreateStmt:
 							puts("creating bootstrap relation");
 						tupdesc = CreateTupleDesc(numattr,attrtypes);
 						reldesc = heap_create(LexIDStr($3), tupdesc,
-											  false, false);
+											  false, false, true);
 						if (DebugMode)
 							puts("bootstrap relation created ok");
 					}
@@ -230,6 +231,19 @@ Boot_DeclareIndexStmt:
 				}
 		;
 
+Boot_DeclareUniqueIndexStmt:
+		  XDECLARE UNIQUE INDEX boot_ident ON boot_ident USING boot_ident LPAREN boot_index_params RPAREN
+				{
+					DO_START;
+
+					DefineIndex(LexIDStr($6),
+								LexIDStr($4),
+								LexIDStr($8),
+								$10, NIL, 1, 0, 0, NIL);
+					DO_END;
+				}
+		;
+
 Boot_BuildIndsStmt:
 		  XBUILD INDICES		{ build_indices(); }
 

src/backend/bootstrap/bootscanner.l

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootscanner.l,v 1.15 1999/09/11 22:26:41 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootscanner.l,v 1.16 1999/11/04 08:00:58 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -90,6 +90,7 @@ insert			{ return(INSERT_TUPLE); }
 "declare"		{ return(XDECLARE); }
 "build"			{ return(XBUILD); }
 "indices"		{ return(INDICES); }
+"unique"		{ return(UNIQUE); }
 "index"			{ return(INDEX); }
 "on"			{ return(ON); }
 "using"			{ return(USING); }

src/backend/catalog/genbki.sh.in

@@ -10,7 +10,7 @@
 #
 #
 # IDENTIFICATION
-#    $Header: /cvsroot/pgsql/src/backend/catalog/Attic/genbki.sh.in,v 1.3 1999/06/04 21:12:06 tgl Exp $
+#    $Header: /cvsroot/pgsql/src/backend/catalog/Attic/genbki.sh.in,v 1.4 1999/11/04 08:00:56 inoue Exp $
 #
 # NOTES
 #    non-essential whitespace is removed from the generated file.
@@ -164,6 +164,20 @@ raw == 1 	{ print; next; }
 	print "declare index " data
 }
 
+/^DECLARE_UNIQUE_INDEX\(/ {
+# ----
+#  end any prior catalog data insertions before starting a define unique index
+# ----
+	if (reln_open == 1) {
+#		print "show";
+		print "close " catalog;
+		reln_open = 0;
+	}
+
+	data = substr($0, 22, length($0) - 22);
+	print "declare unique index " data
+}
+
 /^BUILD_INDICES/	{ print "build indices"; }
 	
 # ----------------

src/backend/catalog/heap.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.105 1999/10/26 03:12:33 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.106 1999/11/04 08:00:56 inoue Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -176,7 +176,8 @@ Relation
 heap_create(char *relname,
 			TupleDesc tupDesc,
 			bool isnoname,
-			bool istemp)
+			bool istemp,
+			bool storage_create)
 {
 	unsigned	i;
 	Oid			relid;
@@ -264,7 +265,8 @@ heap_create(char *relname,
 
 	rel = (Relation) palloc(len);
 	MemSet((char *) rel, 0, len);
-
+	rel->rd_fd = -1;		/* table is not open */
+	rel->rd_unlinked = TRUE;	/* table is not created yet */
 	/*
 	 * create a new tuple descriptor from the one passed in
 	 */
@@ -316,9 +318,9 @@ heap_create(char *relname,
 	 * ----------------
 	 */
 
-	rel->rd_nonameunlinked = TRUE;		/* change once table is created */
-	rel->rd_fd = (File) smgrcreate(DEFAULT_SMGR, rel);
-	rel->rd_nonameunlinked = FALSE;
+	/* smgrcreate() is moved to heap_storage_create() */
+	if (storage_create)
+		heap_storage_create(rel);
 
 	RelationRegisterRelation(rel);
 
@@ -334,6 +336,19 @@ heap_create(char *relname,
 	return rel;
 }
 
+bool
+heap_storage_create(Relation rel)
+{
+	bool smgrcall = false;
+
+	if (rel->rd_unlinked)
+	{
+		rel->rd_fd = (File) smgrcreate(DEFAULT_SMGR, rel);
+		rel->rd_unlinked = FALSE;
+		smgrcall = true;
+	}
+	return smgrcall;
+}
 
 /* ----------------------------------------------------------------
  *		heap_create_with_catalog		- Create a cataloged relation
@@ -795,16 +810,26 @@ heap_create_with_catalog(char *relname,
 	}
 
 	/* ----------------
-	 *	ok, relation does not already exist so now we
-	 *	create an uncataloged relation and pull its relation oid
-	 *	from the newly formed relation descriptor.
+	 *	get_temp_rel_by_name() couldn't check the simultaneous
+	 *	creation. Uniqueness will be really checked by unique
+	 *	indexes of system tables but we couldn't check it here.
+	 *	We have to pospone to create the disk file for this
+	 *	relation.
+	 *	Another boolean parameter "storage_create" was added
+	 *	to heap_create() function. If the parameter is false
+	 *	heap_create() only registers an uncataloged relation
+	 *	to relation cache and heap_storage_create() should be
+	 *	called later.
+	 *	We could pull its relation oid from the newly formed
+	 *	relation descriptor.
 	 *
-	 *	Note: The call to heap_create() does all the "real" work
-	 *	of creating the disk file for the relation.
-	 *	This changes relname for noname and temp tables.
+	 *	Note: The call to heap_create() changes relname for
+	 *	noname and temp tables.
+	 *	The call to heap_storage_create() does all the "real"
+	 *	work of creating the disk file for the relation.
 	 * ----------------
 	 */
-	new_rel_desc = heap_create(relname, tupdesc, false, istemp);
+	new_rel_desc = heap_create(relname, tupdesc, false, istemp, false);
 
 	new_rel_oid = new_rel_desc->rd_att->attrs[0]->attrelid;
 
@@ -843,6 +868,10 @@ heap_create_with_catalog(char *relname,
 		pfree(temp_relname);
 	}
 
+	/*
+	 * We create the disk file for this relation here
+	 */
+	heap_storage_create(new_rel_desc);
 	/* ----------------
 	 *	ok, the relation has been cataloged, so close our relations
 	 *	and return the oid of the newly created relation.
@@ -1519,10 +1548,10 @@ heap_destroy_with_catalog(char *relname)
 	 *	unlink the relation's physical file and finish up.
 	 * ----------------
 	 */
-	if (!(rel->rd_isnoname) || !(rel->rd_nonameunlinked))
+	if (!(rel->rd_isnoname) || !(rel->rd_unlinked))
 		smgrunlink(DEFAULT_SMGR, rel);
 
-	rel->rd_nonameunlinked = TRUE;
+	rel->rd_unlinked = TRUE;
 
 	/*
 	 * Close relcache entry, but *keep* AccessExclusiveLock on the
@@ -1548,9 +1577,9 @@ void
 heap_destroy(Relation rel)
 {
 	ReleaseRelationBuffers(rel);
-	if (!(rel->rd_isnoname) || !(rel->rd_nonameunlinked))
+	if (!(rel->rd_isnoname) || !(rel->rd_unlinked))
 		smgrunlink(DEFAULT_SMGR, rel);
-	rel->rd_nonameunlinked = TRUE;
+	rel->rd_unlinked = TRUE;
 	heap_close(rel, NoLock);
 	RemoveFromNoNameRelList(rel);
 }

src/backend/catalog/index.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/index.c,v 1.93 1999/11/01 02:29:24 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/index.c,v 1.94 1999/11/04 08:00:56 inoue Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -997,7 +997,7 @@ index_create(char *heapRelationName,
 	 * ----------------
 	 */
 	indexRelation = heap_create(indexRelationName,
-								indexTupDesc, false, istemp);
+				indexTupDesc, false, istemp, false);
 
 	/* ----------------
 	 *	  construct the index relation descriptor
@@ -1014,6 +1014,10 @@ index_create(char *heapRelationName,
 	 */
 	indexoid = UpdateRelationRelation(indexRelation, temp_relname);
 
+	/*
+	 * We create the disk file for this relation here
+	 */
+	heap_storage_create(indexRelation);
 	/* ----------------
 	 * Now get the index procedure (only relevant for functional indices).
 	 * ----------------

src/backend/executor/execAmi.c

@@ -5,7 +5,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- *	$Id: execAmi.c,v 1.42 1999/09/18 19:06:47 tgl Exp $
+ *	$Id: execAmi.c,v 1.43 1999/11/04 08:00:57 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -503,7 +503,7 @@ ExecCreatR(TupleDesc tupType,
 		 * heap_create creates a name if the argument to heap_create is
 		 * '\0 '
 		 */
-		relDesc = heap_create(NULL, tupType, true, false);
+		relDesc = heap_create(NULL, tupType, true, false, true);
 	}
 	else
 	{

src/backend/storage/smgr/md.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/smgr/md.c,v 1.57 1999/10/25 03:07:47 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/smgr/md.c,v 1.58 1999/11/04 08:01:00 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -120,6 +120,7 @@ mdcreate(Relation reln)
 				vfd;
 	char	   *path;
 
+	Assert(reln->rd_unlinked && reln->rd_fd < 0);
 	path = relpath(reln->rd_rel->relname.data);
 #ifndef __CYGWIN32__
 	fd = FileNameOpenFile(path, O_RDWR | O_CREAT | O_EXCL, 0600);
@@ -128,28 +129,49 @@ mdcreate(Relation reln)
 #endif
 
 	/*
-	 * If the file already exists and is empty, we pretend that the create
-	 * succeeded.  During bootstrap processing, we skip that check,
-	 * because pg_time, pg_variable, and pg_log get created before their
-	 * .bki file entries are processed.
+	 * During bootstrap processing, we skip that check, because pg_time,
+	 * pg_variable, and pg_log get created before their .bki file entries
+	 * are processed.
 	 *
-	 * As the result of this pretence it was possible to have in pg_class > 1
-	 * records with the same relname. Actually, it should be fixed in
-	 * upper levels, too, but... -	vadim 05/06/97
+	 * For cataloged relations,pg_class is guaranteed to have an unique
+	 * record with the same relname by the unique index.
+	 * So we are able to reuse existent files for new catloged relations.
+	 * Currently we reuse them in the following cases.
+	 * 1. they are empty.
+	 * 2. they are used for Index relations and their size == BLCKSZ * 2.
 	 */
 
 	if (fd < 0)
 	{
-		if (!IsBootstrapProcessingMode())
+		if (!IsBootstrapProcessingMode() &&
+			reln->rd_rel->relkind == RELKIND_UNCATALOGED)
 			return -1;
+
 #ifndef __CYGWIN32__
-		fd = FileNameOpenFile(path, O_RDWR, 0600);		/* Bootstrap */
+		fd = FileNameOpenFile(path, O_RDWR, 0600);
 #else
-		fd = FileNameOpenFile(path, O_RDWR | O_BINARY, 0600);	/* Bootstrap */
+		fd = FileNameOpenFile(path, O_RDWR | O_BINARY, 0600);
 #endif
 		if (fd < 0)
 			return -1;
+		if (!IsBootstrapProcessingMode())
+		{
+			bool	reuse = false;	
+			int	len = FileSeek(fd, 0L, SEEK_END);
+
+			if (len == 0)
+				reuse = true;
+			else if (reln->rd_rel->relkind == RELKIND_INDEX &&
+				 len == BLCKSZ * 2)
+				reuse = true;
+			if (!reuse)
+			{
+				FileClose(fd);
+				return -1;
+			}
+		}
 	}
+	reln->rd_unlinked = false;
 
 	vfd = _fdvec_alloc();
 	if (vfd < 0)
@@ -176,6 +198,11 @@ mdunlink(Relation reln)
 	MdfdVec    *v;
 	MemoryContext oldcxt;
 
+	/* If the relation is already unlinked,we have nothing to do
+	 * any more.
+	 */
+	if (reln->rd_unlinked && reln->rd_fd < 0)
+		return SM_SUCCESS;
 	/*
 	 * Force all segments of the relation to be opened, so that we
 	 * won't miss deleting any of them.
@@ -218,8 +245,9 @@ mdunlink(Relation reln)
 
 	_fdvec_free(fd);
 
-	/* be sure to mark relation closed */
+	/* be sure to mark relation closed && unlinked */
 	reln->rd_fd = -1;
+	reln->rd_unlinked = true;
 
 	return SM_SUCCESS;
 }
@@ -290,6 +318,7 @@ mdopen(Relation reln)
 	int			fd;
 	int			vfd;
 
+	Assert(reln->rd_fd < 0);
 	path = relpath(reln->rd_rel->relname.data);
 
 #ifndef __CYGWIN32__
@@ -311,10 +340,14 @@ mdopen(Relation reln)
 		}
 		if (fd < 0)
 		{
-			elog(ERROR, "mdopen: couldn't open %s: %m", path);
+			elog(NOTICE, "mdopen: couldn't open %s: %m", path);
+			/* mark relation closed and unlinked */
+			reln->rd_fd = -1;
+			reln->rd_unlinked = true;
 			return -1;
 		}
 	}
+	reln->rd_unlinked = false;
 
 	vfd = _fdvec_alloc();
 	if (vfd < 0)

src/backend/storage/smgr/smgr.c

@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/smgr/smgr.c,v 1.29 1999/09/02 02:57:49 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/smgr/smgr.c,v 1.30 1999/11/04 08:01:01 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -182,7 +182,8 @@ smgropen(int16 which, Relation reln)
 {
 	int			fd;
 
-	if ((fd = (*(smgrsw[which].smgr_open)) (reln)) < 0)
+	if ((fd = (*(smgrsw[which].smgr_open)) (reln)) < 0 &&
+		!reln->rd_unlinked)
 		elog(ERROR, "cannot open %s", reln->rd_rel->relname.data);
 
 	return fd;

src/backend/utils/cache/relcache.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.74 1999/10/03 23:55:33 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.75 1999/11/04 08:00:59 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1065,7 +1065,7 @@ RelationIdCacheGetRelation(Oid relationId)
 		if (rd->rd_fd == -1)
 		{
 			rd->rd_fd = smgropen(DEFAULT_SMGR, rd);
-			Assert(rd->rd_fd != -1);
+			Assert(rd->rd_fd != -1 || rd->rd_unlinked);
 		}
 
 		RelationIncrementReferenceCount(rd);
@@ -1099,7 +1099,7 @@ RelationNameCacheGetRelation(char *relationName)
 		if (rd->rd_fd == -1)
 		{
 			rd->rd_fd = smgropen(DEFAULT_SMGR, rd);
-			Assert(rd->rd_fd != -1);
+			Assert(rd->rd_fd != -1 || rd->rd_unlinked);
 		}
 
 		RelationIncrementReferenceCount(rd);
@@ -1613,10 +1613,10 @@ RelationPurgeLocalRelation(bool xactCommitted)
 			 */
 			if (reln->rd_isnoname)
 			{
-				if (!(reln->rd_nonameunlinked))
+				if (!(reln->rd_unlinked))
 				{
 					smgrunlink(DEFAULT_SMGR, reln);
-					reln->rd_nonameunlinked = TRUE;
+					reln->rd_unlinked = TRUE;
 				}
 			}
 			else

src/include/catalog/catversion.h

@@ -36,7 +36,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: catversion.h,v 1.1 1999/10/24 20:42:26 tgl Exp $
+ * $Id: catversion.h,v 1.2 1999/11/04 08:01:06 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -51,6 +51,6 @@
  * catalog changes on the same day...)
  */
 
-#define CATALOG_VERSION_NO	199910241
+#define CATALOG_VERSION_NO	199911041
 
 #endif

src/include/catalog/heap.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: heap.h,v 1.24 1999/10/26 03:12:37 momjian Exp $
+ * $Id: heap.h,v 1.25 1999/11/04 08:01:04 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -23,7 +23,8 @@ typedef struct RawColumnDefault
 
 extern Oid RelnameFindRelid(char *relname);
 extern Relation heap_create(char *relname, TupleDesc att,
-			    bool isnoname, bool istemp);
+			    bool isnoname, bool istemp, bool storage_create);
+extern bool heap_storage_create(Relation rel);
 
 extern Oid heap_create_with_catalog(char *relname, TupleDesc tupdesc, 
 				    char relkind, bool istemp);

src/include/catalog/indexing.h

@@ -7,7 +7,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: indexing.h,v 1.27 1999/11/01 04:00:57 momjian Exp $
+ * $Id: indexing.h,v 1.28 1999/11/04 08:01:06 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -119,11 +119,11 @@ DECLARE_INDEX(pg_index_indexrelid_index on pg_index using btree(indexrelid oid_o
 DECLARE_INDEX(pg_proc_oid_index on pg_proc using btree(oid oid_ops));
 DECLARE_INDEX(pg_proc_proname_narg_type_index on pg_proc using btree(proname name_ops, pronargs int2_ops, proargtypes oid8_ops));
 
-DECLARE_INDEX(pg_type_oid_index on pg_type using btree(oid oid_ops));
-DECLARE_INDEX(pg_type_typname_index on pg_type using btree(typname name_ops));
+DECLARE_UNIQUE_INDEX(pg_type_oid_index on pg_type using btree(oid oid_ops));
+DECLARE_UNIQUE_INDEX(pg_type_typname_index on pg_type using btree(typname name_ops));
 
-DECLARE_INDEX(pg_class_oid_index on pg_class using btree(oid oid_ops));
-DECLARE_INDEX(pg_class_relname_index on pg_class using btree(relname name_ops));
+DECLARE_UNIQUE_INDEX(pg_class_oid_index on pg_class using btree(oid oid_ops));
+DECLARE_UNIQUE_INDEX(pg_class_relname_index on pg_class using btree(relname name_ops));
 
 DECLARE_INDEX(pg_attrdef_adrelid_index on pg_attrdef using btree(adrelid oid_ops));
 

src/include/postgres.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1995, Regents of the University of California
  *
- * $Id: postgres.h,v 1.28 1999/10/25 03:07:55 tgl Exp $
+ * $Id: postgres.h,v 1.29 1999/11/04 08:01:07 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -138,6 +138,7 @@ typedef uint32 CommandId;
 #define DATA(x) extern int errno
 #define DESCR(x) extern int errno
 #define DECLARE_INDEX(x) extern int errno
+#define DECLARE_UNIQUE_INDEX(x) extern int errno
 
 #define BUILD_INDICES
 #define BOOTSTRAP

src/include/utils/rel.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: rel.h,v 1.27 1999/09/29 16:06:28 wieck Exp $
+ * $Id: rel.h,v 1.28 1999/11/04 08:01:09 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -78,7 +78,7 @@ typedef struct RelationData
 	bool		rd_myxactonly;	/* rel uses the local buffer mgr */
 	bool		rd_isnailed;	/* rel is nailed in cache */
 	bool		rd_isnoname;	/* rel has no name */
-	bool		rd_nonameunlinked;		/* noname rel already unlinked */
+	bool		rd_unlinked;	/* rel already unlinked or not created yet */
 	Form_pg_am	rd_am;			/* AM tuple */
 	Form_pg_class rd_rel;		/* RELATION tuple */
 	Oid			rd_id;			/* relation's object id */