A Level Computer Science 9618 Paper 12, May/June 2023

Allows the sharing of files/data // Allows communication between the devices

Allows the sharing of resources e.g. hardware / software (applications)

Covers a small geographical area

The infrastructure is privately owned // not controlled by external organisations

Each computer directly connected only to the server ...

... all components correctly labelled

A protocol (suite)

For data transmission over standard / universal wired / cabled network connections

Uses Carrier Sense Multiple Access / Collision Detection (CSMA/CD)

The server performs minimal / some processing for the client

The clients also do most of their own processing/work independently // most of the resources are installed locally

Data dictionary: Data about the data in the database // data about the structure of the database // metadata for a database

Query processor: Software that allows the user to enter criteria, then finds and returns the appropriate result // software that processes and executes queries written in SQL

Logical schema: A model of a database that is not specific to one DBMS

Developer interface: A software tool that allows the user to create items such as tables, forms and reports

Referential Integrity makes sure data is consistent

Referential Integrity makes sure all data is up-to-date

Referential integrity ensures that every foreign key has a corresponding primary key

Presence check to make sure that the (rider level) is entered

Look-up / Existence check to make sure the rider level is only Beginner, Intermediate or Advanced

SELECT field Name

FROM table HORSE

WHERE with Intermediate / Beginner

OR with Beginner / Intermediate

SUM should be COUNT // SELECT COUNT(STUDENT.RiderLevel)

The WHERE statement needs the table names before each field name // WHERE STUDENT.StudentID = LESSON.StudentID

The OR should be AND // AND Date = #09/09/2023#

Beginner is missing the speech marks // STUDENT.RiderLevel = "Beginner";

generates object code to second pass

reads source code one line at a time to both boxes

removes white space and adds labels to first pass

Direct addressing

Indirect addressing

Immediate addressing

2^16 // 65536

Working: +120 = 0111 1000

Answer: 1000 0111

Working: A04 = (10 * 16^2) + 4 // A04 = (10 * 256) + 4 // A04 = 1010 0000 0100

Answer: 2564

0011 1100

Interrupt

Timing

Increase number of cores

Each core can independently carry out a process at the same time // so that more instructions are performed in parallel

Increase RAM capacity

... allowing more applications to reside in memory at the same time, saving disk access times

1 bit is transferred at a time // Can be synchronous or asynchronous // USB-3 is full duplex and earlier versions are half-duplex

HDMI // DisplayPort

Manages the scheduling of processes // decides which order to run processes

Manages which resources the processes require

… such as allocating memory

Enables processes to share data

Prevents interference between processes // resolution of conflicts

To help users to set-up / configure / analyse / optimise / maintain the computer ...

... by for example, making memory allocation more efficient // ... by for example, checking the system for faults

correct XOR and AND gates, with correct inputs

correct NOT and NOR gates with correct inputs

first 4 rows (0, 1, 1, 1)

last 4 rows (1, 0, 1, 1)

Set of pre-written / pre-compiled / pre-tested subroutines

... which can be called in other programs

(main) memory requirements for program is reduced

... as dynamic link library is loaded only once / when required

the executable file size of the program using the DLL will be smaller

... because the executable does not contain (all) the library routines

Allows the developer to make real-time changes // so the program can be debugged at each stage // the effect of any changes made by the developer can be seen immediately

The developer can test when incomplete // so small parts can be tested without having to test the rest of the program // if one section does not work others can still be tested // To avoid dependent errors

The developer can debug multiple errors simultaneously // Produces an executable file // so that the developer can test the program multiple times without recompiling

Breakpoints: Stop the code at a specific line to check the current progress / values

Dynamic syntax checks: Highlight / underline / colour syntax errors as the code is entered

Context-sensitive prompts: Suggest the code to add // automatically complete statements

Single stepping: Run the code one line at a time so the values can be checked

Uses speech recognition

... which identifies key phrases / words spoken

… and matches these to a database