Answer:
a. True
Explanation:
The three tiers in a three-tier architecture are:
Presentation Tier: Occupies the top level and displays information related to services available on a website. This tier communicates with other tiers by sending results to the browser and other tiers in the network.
Middle Tier: Also called the application tier, logic tier, business logic or logic tier, this tier is pulled from the presentation tier. It controls application functionality by performing detailed processing.
Data Tier: Houses database servers where information is stored and retrieved. Data in this tier is kept independent of application servers or business logic.
B. To organize information using shapes.
Answer:
The problem that created due to the difference in the model of programming language and the database model.
Explanation:
The practical relational model has three components which are as follows
1. Attributes
2. Datatypes
3. Tuples
To minimize this problem
1. We switch low pass L-Network to high pass L-network
2. We switch high pass L-Network to low pass L-network
3. We use the impedence matching transformer
Well since Windows XP runs on Windows 2000 technology,it would be "slow".Also that Windows XP had MSN,which expired 15 years ago,but the good thing about Windows XP is that it can connect to the internet via WiFi without the computers hardware used for WiFi(PC only).Also that Windows XP has a logo on the start-up screen.Windows Vista on the other hand, doesn't have a logo on the start-up screen,but shows a Windows Vista animated logo atfer the start-up screen.Also that some people named Windows Vista "The first Windows 7".But somewhat,Windows Vista ran faster than Windows XP at starting up.Windows Vista was old,but it sold better than Windows XP.
Answer:
The corrected question is:
Write an SQL statement to display the WarehouseID, the sum of QuantityOnOrder and sum of QuantityOnHand, grouped by WarehouseID and QuantityOnOrder. Name the sum of QuantityOnOrder as TotalItemsOnOrder and the sum of QuantityOnHand as TotalItemsOnHand. Use only the INVENTORY table in your SQL statement.
Answer to this corrected question:
SELECT WarehouseID,
SUM(QuantityOnOrder) AS TotalItemsOnOrder,
SUM(QuantityOnHand) AS TotalItemsOnHand
FROM INVENTORY
GROUP BY WarehouseID, QuantityOnOrder;
According to the given question:
SELECT WarehouseID,
SUM(QuantityOnOrder) + SUM(QuantityOnHand) AS TotalItemsOnHand
FROM INVENTORY
GROUP BY WarehouseID, QuantityOnOrder;
Explanation:
- In the SQL statement SELECT statement is used to select the data from the table. Here the SELECT statement is used to select WarehouseID, Sum of the columns QuantityOnOrder and QuantityOnHand from INVENTORY table.
- The sum of QuantityOnOrder and QuantityOnHand columns are given the name of TotalItemsonHand (In case of the corrected question the sum of column QuantityOnOrder is named as TotalItemsOnOrder and the column QuantityOnHand is named as TotalItemsOnHand
) using Alias AS. Alias is the temporary name given to the columns or table to make them more readable.
- GROUP BY statement is used to arrange or "group" same data and is often use with aggregate functions like SUM function here. So the grouping here is done based on two columns WarehouseID and QuantityOnOrder.
- SUM function in this SQL statement is an aggregate function to calculate the sum of all value in the columns QuantityOnOrder and QuantityOnHand.
