可以使用下面的自定义函数，取消当前节点上的所有共享表的定义：

def existsShareVariable(varName){
     return objs(true).name.find(varName)>=0
}

def ClearAllSharedTables(){
	sharedTables = exec name from objs(true) where form="TABLE", shared=true
	for(sharedTable in sharedTables){
		print("Undef Shared Table: " + sharedTable)
		try{
			undef(sharedTable, SHARED)
		}
		catch(ex){
			print(ex)
		}
	}
	print("All shared table have been cleared !")
}