This patch is for the TODO item

* Disallow LOCK on view

src/backend/commands/command.c is the only affected file

--
Mark Hollomon

diff --git a/src/backend/commands/command.c b/src/backend/commands/command.c
index 054b76e480d1be9d53b51ff59e2df4302a658c55..668858d07725094fbad3a55fc919160d3d20579d 100644 (file)
--- a/src/backend/commands/command.c
+++ b/src/backend/commands/command.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/commands/Attic/command.c,v 1.98 2000/09/06 14:15:16 petere Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/commands/Attic/command.c,v 1.99 2000/09/12 04:30:08 momjian Exp $
  *
  * NOTES
  *       The PerformAddAttribute() code, like most of the relation
@@ -55,6 +55,9 @@
 
 
 static bool needs_toast_table(Relation rel);
+static bool is_view(char *relname, char *command);
+
+
 
 
 /* --------------------------------
@@ -1087,9 +1090,6 @@ void
 AlterTableAddConstraint(char *relationName,
                                                bool inh, Node *newConstraint)
 {
-       char rulequery[41+NAMEDATALEN]; 
-       void *qplan;
-       char nulls[1]="";
 
        if (newConstraint == NULL)
                elog(ERROR, "ALTER TABLE / ADD CONSTRAINT passed invalid constraint.");
@@ -1100,19 +1100,8 @@ AlterTableAddConstraint(char *relationName,
 #endif
 
        /* check to see if the table to be constrained is a view. */
-       sprintf(rulequery, "select * from pg_views where viewname='%s'", relationName);
-       if (SPI_connect()!=SPI_OK_CONNECT)
-               elog(ERROR, "ALTER TABLE: Unable to determine if %s is a view - SPI_connect failure..", relationName);
-        qplan=SPI_prepare(rulequery, 0, NULL);
-       if (!qplan)
-               elog(ERROR, "ALTER TABLE: Unable to determine if %s is a view - SPI_prepare failure.", relationName);
-       qplan=SPI_saveplan(qplan);
-       if (SPI_execp(qplan, NULL, nulls, 1)!=SPI_OK_SELECT) 
-               elog(ERROR, "ALTER TABLE: Unable to determine if %s is a view - SPI_execp failure.", relationName);
-        if (SPI_processed != 0)
-                elog(ERROR, "ALTER TABLE: Cannot add constraints to views.");
-        if (SPI_finish() != SPI_OK_FINISH)
-                elog(NOTICE, "SPI_finish() failed in ALTER TABLE");
+       if (is_view(relationName, "ALTER TABLE"))
+                elog(ERROR, "ALTER TABLE: Cannot add constraints to views.");
                
        switch (nodeTag(newConstraint))
        {
@@ -1261,19 +1250,8 @@ AlterTableAddConstraint(char *relationName,
                                }
 
                                /* check to see if the referenced table is a view. */
-                               sprintf(rulequery, "select * from pg_views where viewname='%s'", fkconstraint->pktable_name);
-                               if (SPI_connect()!=SPI_OK_CONNECT)
-                                       elog(ERROR, "ALTER TABLE: Unable to determine if %s is a view.", relationName);
-                               qplan=SPI_prepare(rulequery, 0, NULL);
-                               if (!qplan)
-                                       elog(ERROR, "ALTER TABLE: Unable to determine if %s is a view.", relationName);
-                               qplan=SPI_saveplan(qplan);
-                               if (SPI_execp(qplan, NULL, nulls, 1)!=SPI_OK_SELECT) 
-                                       elog(ERROR, "ALTER TABLE: Unable to determine if %s is a view.", relationName);
-                               if (SPI_processed != 0)
-                                       elog(ERROR, "ALTER TABLE: Cannot add constraints to views.");
-                               if (SPI_finish() != SPI_OK_FINISH)
-                                       elog(NOTICE, "SPI_finish() failed in RI_FKey_check()");
+                               if (is_view(fkconstraint->pktable_name, "ALTER TABLE"))
+                                elog(ERROR, "ALTER TABLE: Cannot add constraints to views.");
 
                                /*
                                 * Grab an exclusive lock on the pk table, so that someone
@@ -1720,6 +1698,9 @@ LockTableCommand(LockStmt *lockstmt)
        Relation        rel;
        int                     aclresult;
 
+       if (is_view(lockstmt->relname, "LOCK TABLE")) 
+                       elog(ERROR, "LOCK TABLE: cannot lock a view");
+
        rel = heap_openr(lockstmt->relname, NoLock);
 
        if (lockstmt->mode == AccessShareLock)
@@ -1735,3 +1716,29 @@ LockTableCommand(LockStmt *lockstmt)
        heap_close(rel, NoLock);        /* close rel, keep lock */
 }
 
+
+static
+bool
+is_view (char * relname, char *command)
+{
+       bool retval;
+       char rulequery[41+NAMEDATALEN]; 
+       void *qplan;
+       char nulls[1]="";
+
+       sprintf(rulequery, "select * from pg_views where viewname='%s'", relname);
+       if (SPI_connect()!=SPI_OK_CONNECT)
+               elog(ERROR, "%s: Unable to determine if %s is a view - SPI_connect failure..", command, relname);
+       qplan=SPI_prepare(rulequery, 0, NULL);
+       if (!qplan)
+               elog(ERROR, "%s: Unable to determine if %s is a view - SPI_prepare failure.", command, relname);
+       qplan=SPI_saveplan(qplan);
+       if (SPI_execp(qplan, NULL, nulls, 1)!=SPI_OK_SELECT) 
+               elog(ERROR, "%s: Unable to determine if %s is a view - SPI_execp failure.", command, relname);
+
+       retval = (SPI_processed != 0);
+  if (SPI_finish() != SPI_OK_FINISH)
+        elog(NOTICE, "SPI_finish() failed in %s", command);
+
+  return retval;
+}