*** a/src/backend/catalog/pg_depend.c
--- b/src/backend/catalog/pg_depend.c
***************
*** 20,25 ****
--- 20,27 ----
  #include "catalog/indexing.h"
  #include "catalog/pg_constraint.h"
  #include "catalog/pg_depend.h"
+ #include "catalog/pg_extension.h"
+ #include "catalog/pg_namespace.h"
  #include "miscadmin.h"
  #include "utils/fmgroids.h"
  #include "utils/lsyscache.h"
***************
*** 643,645 **** get_index_constraint(Oid indexId)
--- 645,699 ----
  
  	return constraintId;
  }
+ 
+ /*
+  * get_extension_namespace
+  *		Given the OID of an extension, return the OID of the schema it
+  *		depends on, or InvalidOid when not found
+  */
+ Oid
+ get_extension_namespace(Oid extensionId)
+ {
+ 	Oid			nspId = InvalidOid;
+ 	Relation	depRel;
+ 	ScanKeyData key[3];
+ 	SysScanDesc scan;
+ 	HeapTuple	tup;
+ 
+ 	/* Search the dependency table for the index */
+ 	depRel = heap_open(DependRelationId, AccessShareLock);
+ 
+ 	ScanKeyInit(&key[0],
+ 				Anum_pg_depend_classid,
+ 				BTEqualStrategyNumber, F_OIDEQ,
+ 				ObjectIdGetDatum(ExtensionRelationId));
+ 	ScanKeyInit(&key[1],
+ 				Anum_pg_depend_objid,
+ 				BTEqualStrategyNumber, F_OIDEQ,
+ 				ObjectIdGetDatum(extensionId));
+ 	ScanKeyInit(&key[2],
+ 				Anum_pg_depend_objsubid,
+ 				BTEqualStrategyNumber, F_INT4EQ,
+ 				Int32GetDatum(0));
+ 
+ 	scan = systable_beginscan(depRel, DependDependerIndexId, true,
+ 							  SnapshotNow, 3, key);
+ 
+ 	while (HeapTupleIsValid(tup = systable_getnext(scan)))
+ 	{
+ 		Form_pg_depend deprec = (Form_pg_depend) GETSTRUCT(tup);
+ 
+ 		if (deprec->refclassid == NamespaceRelationId &&
+ 			deprec->refobjsubid == 0 &&
+ 			deprec->deptype == DEPENDENCY_NORMAL)
+ 		{
+ 			nspId = deprec->refobjid;
+ 			break;
+ 		}
+ 	}
+ 
+ 	systable_endscan(scan);
+ 	heap_close(depRel, AccessShareLock);
+ 
+ 	return nspId;
+ }
*** a/src/backend/commands/alter.c
--- b/src/backend/commands/alter.c
***************
*** 20,25 ****
--- 20,26 ----
  #include "commands/conversioncmds.h"
  #include "commands/dbcommands.h"
  #include "commands/defrem.h"
+ #include "commands/extension.h"
  #include "commands/proclang.h"
  #include "commands/schemacmds.h"
  #include "commands/tablecmds.h"
***************
*** 186,191 **** ExecAlterObjectSchemaStmt(AlterObjectSchemaStmt *stmt)
--- 187,196 ----
  			AlterConversionNamespace(stmt->object, stmt->newschema);
  			break;
  
+ 		case OBJECT_EXTENSION:
+ 			AlterExtensionNamespace(stmt->object, stmt->newschema);
+ 			break;
+ 
  		case OBJECT_FUNCTION:
  			AlterFunctionNamespace(stmt->object, stmt->objarg, false,
  								   stmt->newschema);
*** a/src/backend/commands/extension.c
--- b/src/backend/commands/extension.c
***************
*** 38,48 ****
--- 38,51 ----
  #include "access/xact.h"
  #include "catalog/dependency.h"
  #include "catalog/indexing.h"
+ #include "catalog/namespace.h"
  #include "catalog/pg_depend.h"
  #include "catalog/pg_extension.h"
  #include "catalog/pg_namespace.h"
  #include "catalog/pg_type.h"
  #include "commands/comment.h"
+ #include "commands/conversioncmds.h"
+ #include "commands/defrem.h"
  #include "commands/extension.h"
  #include "commands/portalcmds.h"
  #include "funcapi.h"
***************
*** 1276,1278 **** pg_extension_objects(PG_FUNCTION_ARGS)
--- 1279,1369 ----
  	releaseDependentObjects(fctx->targetObjects);
  	SRF_RETURN_DONE(funcctx);
  }
+ 
+ /*
+  * Execute ALTER EXTENSION SET SCHEMA
+  */
+ void
+ AlterExtensionNamespace(List *name, const char *newschema)
+ {
+ 	Oid			     extensionOid, nspOid, oldNspOid;
+ 	ObjectAddress   *object;
+ 	ObjectAddresses *targetObjects;
+ 	int i;
+ 
+ 	if (!superuser())
+ 		ereport(ERROR,
+ 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ 				 (errmsg("must be superuser to ALTER EXTENSION"))));
+ 
+ 	Assert(list_length(name) == 1);
+ 	extensionOid = get_extension_oid(strVal(linitial(name)), false);
+ 	nspOid = LookupCreationNamespace(newschema);
+ 
+ 	object = (ObjectAddress *)palloc(sizeof(ObjectAddress));
+ 	object->classId = ExtensionRelationId;
+ 	object->objectId = extensionOid;
+ 	object->objectSubId = 0;
+ 
+ 	oldNspOid = get_extension_namespace(extensionOid);
+ 
+ 	targetObjects = listDependentObjects(object);
+ 
+ 	for (i = 0; i < targetObjects->numrefs; i++)
+ 	{
+ 		ObjectAddress *thisobj = targetObjects->refs + i;
+ 
+ 		/*
+ 		 * Do the SET SCHEMA now.
+ 		 *
+ 		 * We only consider objects that have a namespace and that can exist
+ 		 * without depending on another object (like a table) which will
+ 		 * have its dependencies follow the SET SCHEMA operation.
+ 		 */
+ 		switch (getObjectClass(thisobj))
+ 		{
+ 			case OCLASS_CLASS:
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ 						 errmsg("Relations are not supported.")));
+ 				break;
+ 			case OCLASS_PROC:
+ 				AlterFunctionNamespace_oid(thisobj->objectId, nspOid);
+ 				break;
+ 			case OCLASS_TYPE:
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ 						 errmsg("Types are not supported.")));
+ 				break;
+ 			case OCLASS_CONVERSION:
+ 				AlterConversionNamespace_oid(thisobj->objectId, nspOid);
+ 				break;
+ 			case OCLASS_OPERATOR:
+ 				AlterOperatorNamespace_oid(thisobj->objectId, nspOid);
+ 				break;
+ 			case OCLASS_OPCLASS:
+ 				AlterOpClassNamespace_oid(thisobj->objectId, nspOid);
+ 				break;
+ 			case OCLASS_OPFAMILY:
+ 				AlterOpFamilyNamespace_oid(thisobj->objectId, nspOid);
+ 				break;
+ 			case OCLASS_TSPARSER:
+ 				AlterTSParserNamespace_oid(thisobj->objectId, nspOid);
+ 				break;
+ 			case OCLASS_TSDICT:
+ 				AlterTSDictionaryNamespace_oid(thisobj->objectId, nspOid);
+ 				break;
+ 			case OCLASS_TSTEMPLATE:
+ 				AlterTSTemplateNamespace_oid(thisobj->objectId, nspOid);
+ 				break;
+ 			case OCLASS_TSCONFIG:
+ 				AlterTSConfigurationNamespace_oid(thisobj->objectId, nspOid);
+ 				break;
+ 			default:
+ 				break;
+ 		}
+ 	}
+ 	/* update dependencies to point to the new schema */
+ 	changeDependencyFor(ExtensionRelationId, extensionOid,
+ 						NamespaceRelationId, oldNspOid, nspOid);
+ }
*** a/src/backend/parser/gram.y
--- b/src/backend/parser/gram.y
***************
*** 6138,6143 **** AlterObjectSchemaStmt:
--- 6138,6151 ----
  					n->newschema = $6;
  					$$ = (Node *)n;
  				}
+ 			| ALTER EXTENSION any_name SET SCHEMA name
+ 				{
+ 					AlterObjectSchemaStmt *n = makeNode(AlterObjectSchemaStmt);
+ 					n->objectType = OBJECT_EXTENSION;
+ 					n->object = $3;
+ 					n->newschema = $6;
+ 					$$ = (Node *)n;
+ 				}
  			| ALTER FUNCTION function_with_argtypes SET SCHEMA name
  				{
  					AlterObjectSchemaStmt *n = makeNode(AlterObjectSchemaStmt);
*** a/src/backend/tcop/utility.c
--- b/src/backend/tcop/utility.c
***************
*** 1719,1724 **** CreateCommandTag(Node *parsetree)
--- 1719,1727 ----
  				case OBJECT_DOMAIN:
  					tag = "ALTER DOMAIN";
  					break;
+ 				case OBJECT_EXTENSION:
+ 					tag = "ALTER EXTENSION";
+ 					break;
  				case OBJECT_OPERATOR:
  					tag = "ALTER OPERATOR";
  					break;
*** a/src/include/catalog/dependency.h
--- b/src/include/catalog/dependency.h
***************
*** 238,243 **** extern Oid	get_constraint_index(Oid constraintId);
--- 238,246 ----
  
  extern Oid	get_index_constraint(Oid indexId);
  
+ extern Oid get_extension_namespace(Oid extensionId);
+ 
+ 
  /* in pg_shdepend.c */
  
  extern void recordSharedDependencyOn(ObjectAddress *depender,
*** a/src/include/commands/extension.h
--- b/src/include/commands/extension.h
***************
*** 64,69 **** extern void DropExtension(DropExtensionStmt *stmt);
--- 64,70 ----
  extern Oid get_extension_oid(const char *extname, bool missing_ok);
  extern char *get_extension_name(Oid ext_oid);
  extern void RemoveExtensionById(Oid extId);
+ extern void AlterExtensionNamespace(List *name, const char *newschema);
  
  
  #endif   /* EXTENSION_H */