>From a03ea44bcbd18dd86b9e54ea3c8a1454ed1e0d59 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Fri, 25 Apr 2014 16:32:20 -0300
Subject: [PATCH 23/36] deparse: initial support for ALTER TABLE

---
 src/backend/commands/event_trigger.c | 117 ++++++++++-
 src/backend/commands/tablecmds.c     |   7 +
 src/backend/tcop/deparse_utility.c   | 397 ++++++++++++++++++++++++++++++++++-
 src/backend/tcop/utility.c           |  25 ++-
 src/include/commands/event_trigger.h |   5 +
 src/include/tcop/deparse_utility.h   |   9 +
 6 files changed, 557 insertions(+), 3 deletions(-)

diff --git a/src/backend/commands/event_trigger.c b/src/backend/commands/event_trigger.c
index b351af8..74fe67c 100644
--- a/src/backend/commands/event_trigger.c
+++ b/src/backend/commands/event_trigger.c
@@ -50,6 +50,7 @@ typedef struct EventTriggerQueryState
 	slist_head	SQLDropList;
 	bool		in_sql_drop;
 	MemoryContext cxt;
+	StashedCommand *curcmd;
 	List	   *stash;		/* list of StashedCommand; see deparse_utility.h */
 	bool		in_extension;
 	struct EventTriggerQueryState *previous;
@@ -1041,6 +1042,7 @@ EventTriggerBeginCompleteQuery(void)
 	state->cxt = cxt;
 	slist_init(&(state->SQLDropList));
 	state->in_sql_drop = false;
+	state->curcmd = NULL;
 	state->stash = NIL;
 	state->in_extension = currentEventTriggerState ? currentEventTriggerState->in_extension : false;
 
@@ -1340,6 +1342,113 @@ EventTriggerStashExtensionStop(void)
 		currentEventTriggerState->in_extension = false;
 }
 
+/*
+ * EventTriggerStartRecordingSubcmds
+ * 		Prepare to receive data on a complex DDL command about to be executed
+ *
+ * Note we don't actually stash the object we create here into the "stashed"
+ * list; instead we keep it in curcmd, and only when we're done processing the
+ * subcommands we will add it to the actual stash.
+ *
+ * FIXME -- this API isn't considering the possibility of an ALTER TABLE command
+ * being called reentrantly by an event trigger function.  Do we need stackable
+ * commands at this level?
+ */
+void
+EventTriggerComplexCmdStart(Node *parsetree, ObjectType objtype)
+{
+	MemoryContext	oldcxt;
+	StashedCommand *stashed;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	stashed = palloc(sizeof(StashedCommand));
+
+	stashed->type = SCT_AlterTable;
+	stashed->in_extension = currentEventTriggerState->in_extension;
+
+	stashed->d.alterTable.objectId = InvalidOid;
+	stashed->d.alterTable.objtype = objtype;
+	stashed->d.alterTable.subcmds = NIL;
+	/* XXX is it necessary to have the whole parsetree? probably not ... */
+	stashed->parsetree = copyObject(parsetree);
+
+	currentEventTriggerState->curcmd = stashed;
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+void
+EventTriggerComplexCmdSetOid(Oid objectId)
+{
+	currentEventTriggerState->curcmd->d.alterTable.objectId = objectId;
+}
+
+/*
+ * EventTriggerRecordSubcmd
+ * 		Save data about a single part of a complex DDL command
+ *
+ * Right now we only support ALTER TABLE; there are no other DDL commands that
+ * require this.  (ALTER TYPE can also generate multiple subcommands, but it's
+ * actually parsed as ALTER TABLE, so there is no difference at this level.)
+ */
+void
+EventTriggerRecordSubcmd(Node *subcmd, Oid relid, AttrNumber attnum,
+						 Oid newoid)
+{
+	MemoryContext	oldcxt;
+	StashedATSubcmd *newsub;
+
+	Assert(IsA(subcmd, AlterTableCmd));
+	Assert(OidIsValid(currentEventTriggerState->curcmd->d.alterTable.objectId));
+
+	/*
+	 * If we receive a subcommand intended for a relation other than the one
+	 * we've started the complex command for, ignore it.  This is chiefly
+	 * concerned with inheritance situations: in such cases, alter table
+	 * would dispatch multiple copies of the same command for various things,
+	 * but we're only concerned with the one for the main table.
+	 */
+	if (relid != currentEventTriggerState->curcmd->d.alterTable.objectId)
+		return;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	newsub = palloc(sizeof(StashedATSubcmd));
+	newsub->attnum = attnum;
+	newsub->oid = newoid;
+	newsub->parsetree = copyObject(subcmd);
+
+	currentEventTriggerState->curcmd->d.alterTable.subcmds =
+		lappend(currentEventTriggerState->curcmd->d.alterTable.subcmds, newsub);
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * EventTriggerEndRecordingSubcmds
+ * 		Finish up saving a complex DDL command
+ *
+ * FIXME this API isn't considering the possibility that a xact/subxact is
+ * aborted partway through.  Probably it's best to add an
+ * AtEOSubXact_EventTriggers() to fix this.
+ */
+void
+EventTriggerComplexCmdEnd(void)
+{
+	/* If no subcommands, don't stash anything */
+	if (list_length(currentEventTriggerState->curcmd->d.alterTable.subcmds) != 0)
+	{
+		currentEventTriggerState->stash =
+			lappend(currentEventTriggerState->stash,
+					currentEventTriggerState->curcmd);
+	}
+	else
+		pfree(currentEventTriggerState->curcmd);
+
+	currentEventTriggerState->curcmd = NULL;
+}
+
 Datum
 pg_event_trigger_get_creation_commands(PG_FUNCTION_ARGS)
 {
@@ -1418,7 +1527,8 @@ pg_event_trigger_get_creation_commands(PG_FUNCTION_ARGS)
 
 			MemSet(nulls, 0, sizeof(nulls));
 
-			if (cmd->type == SCT_Basic)
+			if (cmd->type == SCT_Basic ||
+				cmd->type == SCT_AlterTable)
 			{
 				Oid			classId;
 				Oid			objId;
@@ -1432,6 +1542,11 @@ pg_event_trigger_get_creation_commands(PG_FUNCTION_ARGS)
 					classId = get_objtype_catalog_oid(cmd->d.basic.objtype);
 					objId = cmd->d.basic.objectId;
 				}
+				else if (cmd->type == SCT_AlterTable)
+				{
+					classId = get_objtype_catalog_oid(cmd->d.alterTable.objtype);
+					objId = cmd->d.alterTable.objectId;
+				}
 
 				tag = CreateCommandTag(cmd->parsetree);
 				addr.classId = classId;
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 46dcf0e..cab0b0b 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -2728,6 +2728,8 @@ AlterTableInternal(Oid relid, List *cmds, bool recurse)
 
 	rel = relation_open(relid, lockmode);
 
+	EventTriggerComplexCmdSetOid(relid);
+
 	ATController(rel, cmds, recurse, lockmode);
 }
 
@@ -3553,6 +3555,9 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
 			break;
 	}
 
+	EventTriggerRecordSubcmd((Node *) cmd, RelationGetRelid(rel),
+							 colno, newoid);
+
 	/*
 	 * Bump the command counter to ensure the next subcommand in the sequence
 	 * can see the changes so far
@@ -5615,6 +5620,8 @@ ATExecDropColumn(List **wqueue, Relation rel, const char *colName,
  * There is no such command in the grammar, but parse_utilcmd.c converts
  * UNIQUE and PRIMARY KEY constraints into AT_AddIndex subcommands.  This lets
  * us schedule creation of the index at the appropriate time during ALTER.
+ *
+ * Return value is the OID of the new index.
  */
 static Oid
 ATExecAddIndex(AlteredTableInfo *tab, Relation rel,
diff --git a/src/backend/tcop/deparse_utility.c b/src/backend/tcop/deparse_utility.c
index 2412843..040c721 100644
--- a/src/backend/tcop/deparse_utility.c
+++ b/src/backend/tcop/deparse_utility.c
@@ -2846,6 +2846,396 @@ deparse_AlterEnumStmt(Oid objectId, Node *parsetree)
 }
 
 static char *
+deparse_AlterTableStmt(StashedCommand *cmd)
+{
+	ObjTree	   *alterTableStmt;
+	ObjTree	   *tmp;
+	ObjTree	   *tmp2;
+	List	   *dpcontext;
+	Relation	rel;
+	List	   *subcmds = NIL;
+	ListCell   *cell;
+	char	   *command;
+
+	rel = heap_open(cmd->d.alterTable.objectId, AccessShareLock);
+	dpcontext = deparse_context_for(RelationGetRelationName(rel),
+									cmd->d.alterTable.objectId);
+
+	alterTableStmt =
+		new_objtree_VA("ALTER TABLE %{identity}D %{subcmds:, }s", 0);
+	tmp = new_objtree_for_qualname(rel->rd_rel->relnamespace,
+								   RelationGetRelationName(rel));
+	append_object_object(alterTableStmt, "identity", tmp);
+
+	foreach(cell, cmd->d.alterTable.subcmds)
+	{
+		StashedATSubcmd	*substashed = (StashedATSubcmd *) lfirst(cell);
+		AlterTableCmd	*subcmd = (AlterTableCmd *) substashed->parsetree;
+		ObjTree	   *tree;
+
+		Assert(IsA(subcmd, AlterTableCmd));
+
+		switch (subcmd->subtype)
+		{
+			case AT_AddColumn:
+			case AT_AddColumnRecurse:
+				/* XXX need to set the "recurse" bit somewhere? */
+				Assert(IsA(subcmd->def, ColumnDef));
+				tree = deparse_ColumnDef(rel, dpcontext, false,
+										 (ColumnDef *) subcmd->def);
+				tmp = new_objtree_VA("ADD COLUMN %{definition}s",
+									 2, "type", ObjTypeString, "add column",
+									 "definition", ObjTypeObject, tree);
+				subcmds = lappend(subcmds,
+								  new_object_object(NULL, tmp));
+				break;
+
+			case AT_DropColumnRecurse:
+			case AT_ValidateConstraintRecurse:
+			case AT_DropConstraintRecurse:
+			case AT_AddOidsRecurse:
+			case AT_AddIndexConstraint:
+			case AT_ReAddIndex:
+			case AT_ReAddConstraint:
+			case AT_ProcessedConstraint:
+			case AT_ReplaceRelOptions:
+				/* Subtypes used for internal operations; nothing to do here */
+				break;
+
+			case AT_AddColumnToView:
+				/* CREATE OR REPLACE VIEW -- nothing to do here */
+				break;
+
+			case AT_ColumnDefault:
+				if (subcmd->def == NULL)
+				{
+					tmp = new_objtree_VA("ALTER COLUMN %{column}I DROP DEFAULT",
+										 1, "type", ObjTypeString, "drop default");
+				}
+				else
+				{
+					List	   *dpcontext;
+					HeapTuple	attrtup;
+					AttrNumber	attno;
+
+					tmp = new_objtree_VA("ALTER COLUMN %{column}I SET DEFAULT %{definition}s",
+										 1, "type", ObjTypeString, "set default");
+
+					dpcontext = deparse_context_for(RelationGetRelationName(rel),
+													RelationGetRelid(rel));
+					attrtup = SearchSysCacheAttName(RelationGetRelid(rel), subcmd->name);
+					attno = ((Form_pg_attribute) GETSTRUCT(attrtup))->attnum;
+					append_string_object(tmp, "definition",
+										 RelationGetColumnDefault(rel, attno, dpcontext));
+					ReleaseSysCache(attrtup);
+				}
+				append_string_object(tmp, "column", subcmd->name);
+
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_DropNotNull:
+				tmp = new_objtree_VA("ALTER COLUMN %{column}I DROP NOT NULL",
+									 1, "type", ObjTypeString, "drop not null");
+				append_string_object(tmp, "column", subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_SetNotNull:
+				tmp = new_objtree_VA("ALTER COLUMN %{column}I SET NOT NULL",
+									 1, "type", ObjTypeString, "set not null");
+				append_string_object(tmp, "column", subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_SetStatistics:
+				/* not yet */
+				break;
+
+			case AT_SetOptions:
+				/* not yet */
+				break;
+
+			case AT_ResetOptions:
+				/* not yet */
+				break;
+
+			case AT_SetStorage:
+				Assert(IsA(subcmd->def, String));
+				tmp = new_objtree_VA("ALTER COLUMN %{column}I SET STORAGE %{storage}s",
+									 3, "type", ObjTypeString, "set storage",
+									 "column", ObjTypeString, subcmd->name,
+									 "storage", ObjTypeString,
+									 strVal((Value *) subcmd->def));
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_DropColumn:
+				tmp = new_objtree_VA("DROP COLUMN %{column}I",
+									 2, "type", ObjTypeString, "drop column",
+								 "column", ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_AddIndex:
+				{
+					Oid			idxOid = substashed->oid;
+					IndexStmt  *istmt;
+					Relation	idx;
+					const char *idxname;
+					Oid			constrOid;
+
+					Assert(IsA(subcmd->def, IndexStmt));
+					istmt = (IndexStmt *) subcmd->def;
+
+					if (!istmt->isconstraint)
+						break;
+
+					idx = relation_open(idxOid, AccessShareLock);
+					idxname = RelationGetRelationName(idx);
+
+					constrOid = get_relation_constraint_oid(
+						cmd->d.alterTable.objectId, idxname, false);
+
+					tmp = new_objtree_VA("ADD CONSTRAINT %{name}I %{definition}s",
+										 3, "type", ObjTypeString, "add constraint",
+										 "name", ObjTypeString, idxname,
+										 "definition", ObjTypeString,
+										 pg_get_constraintdef_string(constrOid, false));
+					subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+
+					relation_close(idx, AccessShareLock);
+				}
+				break;
+
+			case AT_AddConstraint:
+			case AT_AddConstraintRecurse:
+				{
+					/* XXX need to set the "recurse" bit somewhere? */
+					Oid			constrOid = substashed->oid;
+
+					tmp = new_objtree_VA("ADD CONSTRAINT %{name}I %{definition}s",
+										 3, "type", ObjTypeString, "add constraint",
+										 "name", ObjTypeString, get_constraint_name(constrOid),
+										 "definition", ObjTypeString,
+										 pg_get_constraintdef_string(constrOid, false));
+					subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				}
+				break;
+
+			case AT_AlterConstraint:
+				break;
+
+			case AT_ValidateConstraint:
+				tmp = new_objtree_VA("VALIDATE CONSTRAINT %{constraint}I", 2,
+									 "type", ObjTypeString, "validate constraint",
+									 "constraint", ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_DropConstraint:
+				tmp = new_objtree_VA("DROP CONSTRAINT %{constraint}I", 2,
+									 "type", ObjTypeString, "drop constraint",
+									 "constraint", ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_AlterColumnType:
+				tmp = new_objtree_VA("ALTER COLUMN %{column}I SET DATA TYPE %{datatype}T collate_clause using_clause",
+									 2, "type", ObjTypeString, "alter column type",
+									 "column", ObjTypeString, subcmd->name);
+				/* FIXME figure out correct typid/typmod , collate clause, using_clause */
+				append_object_object(tmp, "datatype",
+									 new_objtree_for_type(INT4OID, -1));
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_AlterColumnGenericOptions:
+				break;
+
+			case AT_ChangeOwner:
+				tmp = new_objtree_VA("OWNER TO %{owner}I",
+									 2, "type", ObjTypeString, "change owner",
+									 "owner",  ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_ClusterOn:
+				tmp = new_objtree_VA("CLUSTER ON %{index}I", 2,
+									 "type", ObjTypeString, "cluster on",
+									 "index", ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_DropCluster:
+				tmp = new_objtree_VA("SET WITHOUT CLUSTER", 1,
+									 "type", ObjTypeString, "set without cluster");
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_AddOids:
+				tmp = new_objtree_VA("SET WITH OIDS", 1,
+									 "type", ObjTypeString, "set with oids");
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_DropOids:
+				tmp = new_objtree_VA("SET WITHOUT OIDS", 1,
+									 "type", ObjTypeString, "set without oids");
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_SetTableSpace:
+				tmp = new_objtree_VA("SET TABLESPACE %{tablespace}I", 2,
+									 "type", ObjTypeString, "set tablespace",
+									 "tablespace", ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_SetRelOptions:
+				break;
+
+			case AT_ResetRelOptions:
+				break;
+
+				/*
+				 * FIXME --- should we unify representation of all these
+				 * ENABLE/DISABLE TRIGGER commands??
+				 */
+			case AT_EnableTrig:
+				tmp = new_objtree_VA("ENABLE TRIGGER %{trigger}I", 2,
+									 "type", ObjTypeString, "enable trigger",
+									 "trigger", ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_EnableAlwaysTrig:
+				tmp = new_objtree_VA("ENABLE ALWAYS TRIGGER %{trigger}I", 2,
+									 "type", ObjTypeString, "enable always trigger",
+									 "trigger", ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_EnableReplicaTrig:
+				tmp = new_objtree_VA("ENABLE REPLICA TRIGGER %{trigger}I", 2,
+									 "type", ObjTypeString, "enable replica trigger",
+									 "trigger", ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_DisableTrig:
+				tmp = new_objtree_VA("DISABLE TRIGGER %{trigger}I", 2,
+									 "type", ObjTypeString, "disable trigger",
+									 "trigger", ObjTypeString, subcmd->name);
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_EnableTrigAll:
+				tmp = new_objtree_VA("ENABLE TRIGGER ALL", 1,
+									 "type", ObjTypeString, "enable trigger all");
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_DisableTrigAll:
+				tmp = new_objtree_VA("DISABLE TRIGGER ALL", 1,
+									 "type", ObjTypeString, "disable trigger all");
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_EnableTrigUser:
+				tmp = new_objtree_VA("ENABLE TRIGGER USER", 1,
+									 "type", ObjTypeString, "enable trigger user");
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_DisableTrigUser:
+				tmp = new_objtree_VA("DISABLE TRIGGER USER", 1,
+									 "type", ObjTypeString, "disable trigger user");
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_EnableRule:
+				break;
+
+			case AT_EnableAlwaysRule:
+				break;
+
+			case AT_EnableReplicaRule:
+				break;
+
+			case AT_DisableRule:
+				break;
+
+			case AT_AddInherit:
+				/*
+				 * XXX this case is interesting: we cannot rely on parse node
+				 * because parent name might be unqualified; but there's no way
+				 * to extract it from catalog either, since we don't know which
+				 * of the parents is the new one.
+				 */
+				break;
+
+			case AT_DropInherit:
+				/* XXX ditto ... */
+				break;
+
+			case AT_AddOf:
+				break;
+
+			case AT_DropOf:
+				break;
+
+			case AT_ReplicaIdentity:
+				tmp = new_objtree_VA("REPLICA IDENTITY %{ident}s", 1,
+									 "type", ObjTypeString, "replica identity");
+				switch (((ReplicaIdentityStmt *) subcmd->def)->identity_type)
+				{
+					case REPLICA_IDENTITY_DEFAULT:
+						append_string_object(tmp, "ident", "DEFAULT");
+						break;
+					case REPLICA_IDENTITY_FULL:
+						append_string_object(tmp, "ident", "FULL");
+						break;
+					case REPLICA_IDENTITY_NOTHING:
+						append_string_object(tmp, "ident", "NOTHING");
+						break;
+					case REPLICA_IDENTITY_INDEX:
+						tmp2 = new_objtree_VA("USING INDEX %{index}I", 1,
+											  "index", ObjTypeString,
+											  ((ReplicaIdentityStmt *) subcmd->def)->name);
+						append_object_object(tmp, "ident", tmp2);
+						break;
+				}
+				subcmds = lappend(subcmds, new_object_object(NULL, tmp));
+				break;
+
+			case AT_GenericOptions:
+				break;
+
+			default:
+				elog(WARNING, "unsupported alter table subtype %d",
+					 subcmd->subtype);
+				break;
+		}
+	}
+
+	if (list_length(subcmds) == 0)
+	{
+		command = NULL;
+	}
+	else
+	{
+		append_array_object(alterTableStmt, "subcmds", subcmds);
+		command = jsonize_objtree(alterTableStmt);
+	}
+
+	free_objtree(alterTableStmt);
+	heap_close(rel, AccessShareLock);
+
+	return command;
+}
+
+static char *
 deparse_parsenode_cmd(StashedCommand *cmd)
 {
 	Oid			objectId;
@@ -2859,6 +3249,10 @@ deparse_parsenode_cmd(StashedCommand *cmd)
 		case SCT_Basic:
 			objectId = cmd->d.basic.objectId;
 			break;
+		case SCT_AlterTable:
+			/* XXX needed? */
+			objectId = cmd->d.alterTable.objectId;
+			break;
 		default:
 			elog(ERROR, "unexpected deparse node type %d", cmd->type);
 	}
@@ -2954,7 +3348,7 @@ deparse_parsenode_cmd(StashedCommand *cmd)
 			break;
 
 		case T_AlterTableStmt:
-			command = NULL;
+			command = deparse_AlterTableStmt(cmd);
 			break;
 
 		case T_AlterEnumStmt:
@@ -3013,6 +3407,7 @@ deparse_utility_command(StashedCommand *cmd)
 	switch (cmd->type)
 	{
 		case SCT_Basic:
+		case SCT_AlterTable:
 			command = deparse_parsenode_cmd(cmd);
 			break;
 		default:
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index beedb01..03547a6 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -982,6 +982,10 @@ ProcessUtilitySlow(Node *parsetree,
 						stmts = transformAlterTableStmt(relid, atstmt,
 														queryString);
 
+						/* ... ensure we have an event trigger context ... */
+						EventTriggerComplexCmdStart(parsetree, atstmt->relkind);
+						EventTriggerComplexCmdSetOid(relid);
+
 						/* ... and do it */
 						foreach(l, stmts)
 						{
@@ -995,19 +999,32 @@ ProcessUtilitySlow(Node *parsetree,
 							}
 							else
 							{
-								/* Recurse for anything else */
+								/*
+								 * Recurse for anything else.  If we need to do
+								 * so, "close" the current complex-command set,
+								 * and start a new one at the bottom; this is
+								 * needed to ensure the ordering of queued
+								 * commands is consistent with the way they are
+								 * executed here.
+								 */
+								EventTriggerComplexCmdEnd();
 								ProcessUtility(stmt,
 											   queryString,
 											   PROCESS_UTILITY_SUBCOMMAND,
 											   params,
 											   None_Receiver,
 											   NULL);
+								EventTriggerComplexCmdStart(parsetree, atstmt->relkind);
+								EventTriggerComplexCmdSetOid(relid);
 							}
 
 							/* Need CCI between commands */
 							if (lnext(l) != NULL)
 								CommandCounterIncrement();
 						}
+
+						/* done */
+						EventTriggerComplexCmdEnd();
 					}
 					else
 						ereport(NOTICE,
@@ -1156,6 +1173,7 @@ ProcessUtilitySlow(Node *parsetree,
 					stmt = transformIndexStmt(relid, stmt, queryString);
 
 					/* ... and do it */
+					EventTriggerComplexCmdStart(parsetree, OBJECT_INDEX);	/* relkind? */
 					objectId =
 						DefineIndex(relid,	/* OID of heap relation */
 									stmt,
@@ -1166,6 +1184,7 @@ ProcessUtilitySlow(Node *parsetree,
 									false); /* quiet */
 					EventTriggerStashCommand(objectId, OBJECT_INDEX,
 											 parsetree);
+					EventTriggerComplexCmdEnd();
 				}
 				break;
 
@@ -1249,8 +1268,10 @@ ProcessUtilitySlow(Node *parsetree,
 				break;
 
 			case T_ViewStmt:	/* CREATE VIEW */
+				EventTriggerComplexCmdStart(parsetree, OBJECT_VIEW);	/* XXX relkind? */
 				objectId = DefineView((ViewStmt *) parsetree, queryString);
 				EventTriggerStashCommand(objectId, OBJECT_VIEW, parsetree);
+				EventTriggerComplexCmdEnd();
 				break;
 
 			case T_CreateFunctionStmt:	/* CREATE FUNCTION */
@@ -1377,7 +1398,9 @@ ProcessUtilitySlow(Node *parsetree,
 				break;
 
 			case T_AlterTableSpaceMoveStmt:
+				EventTriggerComplexCmdStart(parsetree, OBJECT_TABLE);	/* XXX relkind? */
 				AlterTableSpaceMove((AlterTableSpaceMoveStmt *) parsetree);
+				EventTriggerComplexCmdEnd();
 				break;
 
 			case T_AlterOwnerStmt:
diff --git a/src/include/commands/event_trigger.h b/src/include/commands/event_trigger.h
index 8ddca3d..3e84cf7 100644
--- a/src/include/commands/event_trigger.h
+++ b/src/include/commands/event_trigger.h
@@ -56,5 +56,10 @@ extern void EventTriggerStashExtensionStart(void);
 extern void EventTriggerStashExtensionStop(void);
 extern void EventTriggerStashCommand(Oid objectId, ObjectType objtype,
 						 Node *parsetree);
+extern void EventTriggerComplexCmdStart(Node *parsetree, ObjectType objtype);
+extern void EventTriggerComplexCmdSetOid(Oid objectId);
+extern void EventTriggerRecordSubcmd(Node *subcmd, Oid relid,
+						 AttrNumber attnum, Oid newoid);
+extern void EventTriggerComplexCmdEnd(void);
 
 #endif   /* EVENT_TRIGGER_H */
diff --git a/src/include/tcop/deparse_utility.h b/src/include/tcop/deparse_utility.h
index 865e018..37b38f0 100644
--- a/src/include/tcop/deparse_utility.h
+++ b/src/include/tcop/deparse_utility.h
@@ -26,6 +26,7 @@
 typedef enum StashedCommandType
 {
 	SCT_Basic,
+	SCT_AlterTable
 } StashedCommandType;
 
 /*
@@ -42,6 +43,7 @@ typedef struct StashedCommand
 {
 	StashedCommandType type;
 	bool		in_extension;
+	List	   *subcmds;	/* list of StashedATSubcmd */
 	Node	   *parsetree;
 
 	union
@@ -51,6 +53,13 @@ typedef struct StashedCommand
 			Oid			objectId;
 			ObjectType	objtype;
 		} basic;
+
+		struct AlterTableCommand
+		{
+			Oid		objectId;
+			ObjectType objtype;
+			List   *subcmds;
+		} alterTable;
 	} d;
 } StashedCommand;
 
-- 
1.9.1

