Since there are two count, then we must simply compare them. I generally take atoms on the molecular queries, so I will have to retain each statement in the view. Then, I connected with RecipeID field conditions do create a third view, the addition of a condition that is available must be equal in need. To make this list more attractive, I also added to Recipes to go inside the table, so I can get the recipe name. You can see Listing B. You can also get rid of this logic to see the recipes, you can change the condition WHERE statement Required Available, but this does not simplify the operation. / * Count the ingredients required * / SELECT [Recipe Ingredients]. RecipeID, Count AS RequiredFROM [Recipe Ingredients] GROUP BY [Recipe Ingredients]. RecipeID; / * count the ingredients available * / SELECT [Recipe Ingredients]. RecipeID, Count AS AvailableFROM Pantry RIGHT JOIN [Recipe Ingredients] ON Pantry.IngredientID = [Recipe Ingredients]. IngredientIDGROUP BY [Recipe Ingredients]. RecipeID; SELECT IngredientsRequired_by_Recipe_qs.RecipeID, Recipes.RecipeNameFROMINNER JOIN Recipes ON IngredientsRequired_by_Recipe_qs.RecipeID = Recipes.RecipeIDWHERE);
Target ip of the mac address is how to obtain it? Ethernet originator host will send a copy to each host that contains the destination ip address of the Ethernet data frame, and look forward to the destination host response, resulting in the corresponding mac address of the destination host, and the mac address into their own within an arp cache. When the LAN hosts are connected through the HUB, etc., generally referred to as shared connection, this shared connection has a very obvious feature: that HUB will receive all the data on each to the HUB port forwarding, that is based on mac addresses when the host sends a packet, although this sender host address of the target host, but that does not mean that in a network host can not hear the other side of the transmitter and receiver communication between, but in normal circumstances would be to ignore these other host communication messages only! If the hosts do not want to ignore these messages, network card is set to the promiscuous state, then, for this hosts network interface, any transmission of this information is within the LAN can be heard. Let us look at an example: we now have A, B two hosts connected through an Ethernet hub, the present A machine on a user wants to access WWW services provided by the B machine, then when A Machine Users type in the browser the ip address of B, B machine provided by web services, from 7 point of view layer structure have taken place in what?