ING_DB

WEGA/contrib/ingres/dbs/src/dbu/destroy.c

@@ -0,0 +1,143 @@
+# include	"gen.h"
+# include	"../h/dbs.h"
+# include	"../h/aux.h"
+# include	"../h/catalog.h"
+# include	"../h/lock.h"
+
+extern int	Standalone;
+
+/*
+**  DESTROY RELATION
+**
+**	The relations in pv are destroyed.  This involves three steps:
+**	1 - remove tuple from relation relation
+**	2 - remove tuples from attribute relation
+**	3 - unlink physical file
+**
+**	If the relation is a secondary index, the entry is removed
+**	from the index relation, and the primary relation is set to
+**	be "not indexed" (unless there is another index on it).
+**
+**	If the relation has an index, all its indexes are also
+**	destroyed.
+**
+**	If any errors occured while destroying the relations,
+**	then the last error number is returned, otherwise
+**	0 is returned.
+**
+**	If any query modification was defined on the relation,
+**	the qrymod catalogues are updated.
+**
+**	If the Standalone variable is non-zero, relation names to
+**	destroy include the owner, and you need not own the relation.
+**	This is used by purge.
+*/
+destroy(pc, pv)
+int	pc;
+char	**pv;
+{
+	register int	i;
+	register int	ret;
+	register char	*name;
+
+	opencatalog(AA_REL, 2);
+	opencatalog(AA_ATT, 2);
+
+	for (ret = 0; (name = *pv++) != (char *) -1; )
+	{
+		if (i = des(name))
+			ret = i;
+	}
+	return (ret);
+}
+
+
+des(name)
+char	*name;
+{
+	register int		i;
+	register char		*relname;
+	struct tup_id		tid;
+	char			newrelname[MAXNAME + 3];
+	extern DESC		Reldes;
+	extern DESC		Attdes;
+	extern DESC		Inddes;
+	extern DESC		Treedes;
+	struct relation		relt;
+	struct relation		relk;
+	extern char		*AArelpath();
+
+	relname = name;
+#	ifdef xZTR1
+	AAtTfp(3, -1, "DESTROY: %s\n", relname);
+#	endif
+
+	newrelname[MAXNAME + 2] = 0;
+
+	/* get the tuple from relation relation */
+	AAam_setkey(&Reldes, &relk, relname, RELID);
+	if (Standalone)
+		AAam_setkey(&Reldes, &relk, &relname[MAXNAME], RELOWNER);
+	else
+		AAam_setkey(&Reldes, &relk, AAusercode, RELOWNER);
+	if (i = AAgetequal(&Reldes, &relk, &relt, &tid))
+	{
+		if (i < 0)
+			AAsyserr(11019, relname, i);
+		/* nonexistant relation */
+		return (error(5202, relname, (char *) 0));
+	}
+
+	/* don't allow a system relation to be destroyed */
+	if (relt.relstat & S_CATALOG)
+	{
+		/* attempt to destroy system catalog */
+		return (error(5201, relname, (char *) 0));
+	}
+
+	/* check if relation in use */
+	if (AAsetrll(A_RTN, tid, M_EXCL) < 0)
+		goto use_error;
+	if (AAsetusl(A_RTN, tid, M_EXCL) < 0)
+	{
+		AAunlrl(tid);
+use_error:
+		return (error(5205, relname, (char *) 0));
+	}
+
+	if (i = AAam_delete(&Reldes, &tid))
+		AAsyserr(11020, i);
+
+	/*
+	** for concurrency reasons, flush the relation-relation page
+	** where the tuple was just deleted. This will prevent anyone
+	** from being able to "AArelopen" the relation while it is being
+	** destroyed. It also allows recovery to finish the destroy
+	** it the system crashes during this destroy.
+	*/
+	if (i = AAam_flush_rel(&Reldes, FALSE))
+		AAsyserr(11021, i);
+	AAunlus(tid);
+	AAunlrl(tid);
+
+	purgetup(&Attdes, relt.relid, ATTRELID, relt.relowner, ATTOWNER);
+
+	/*
+	**	If this is a user relation, then additional processing
+	**	might be needed to clean up indicies, protection constraints
+	**	etc.
+	*/
+	if (!(relt.relstat & S_CATALOG))
+		userdestroy(&relt);
+
+	if (!(relt.relstat & S_VIEW))
+	{
+		if (Standalone)
+			AAbmove(relname, newrelname, MAXNAME + 2);
+		else
+			AAdbname(relname, AAusercode, newrelname);
+		if (unlink(AArelpath(newrelname)) < 0)
+			AAsyserr(11022, newrelname);
+	}
+	return (0);
+}