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Questions A Data is to be stored in a structure and to do this a data type must be chosen for each item of data. Choose a suitable data type from the following list for the data shown in the table: Logical/Boolean Alphanumeric Numeric Date without dots is just words Name of Field Title Phone number Sex Country Data of Birth Years at address 2. Example data (Mr,Mrs,Ms,Dr,etc.) 155-6655-1173 M or F Botswana 01/10/03 4 Data type alphanumeric/text alphanumeric(with Dash) logical/Boolean words Data numeric Here is a list of examples of data to be put into a structure Some of this data can have the logical? Boolean data type and some of it cannot. Complete the following table by placing a tick in the box next to those items of data that could use a logical/Boolean data type. Items of data Driving license ( yes or no ) Sex ( M or F) Size( S,M,L,XL,XXL) Airport code (PEK,ICN,YNT) Car registration number Data of purchase Car type (manual or automatic) Tick if data type if logical/ Boolean * * x x x x * Furl type ( diesel or petrol) are you hungry? is your name long or short? * x x Items of Data Driving License(Y or N) Size (S,M,L,XL) Sex (M or F) Airport Code (PEK, ICN, YNT) Car Reg Number Date of Purchase Car Type (Manual/Automatic) Fuel Type (Diesel/petrol) Are you Hungry? Is your name long or short? Tick if Logical/Boolean Not Logical/Boolean Logical/Boolean Logical/Boolean Not Logical/Boolean Not Logical/Boolean Not Logical/Boolean Logical/Boolean Logical/Boolean Not Logical/Boolean Not Logical/Boolean Question B 1 A luxury car rental firm keeps the details of the cars it rents out in a table. The structure and contents of this table are shown below. Reg-number Make Model DB51 AML Aston Martin DB7 CAB 360M Ferrari 360 Modena GT X34 FER Ferrari 355 Spider MAS 12 Maserati 3200GTA FG09 FRT Porsche 911Turbo M3 MMM BMW M3 Conv T433 YTH Jaguar XK8 a Give the names of two fields shown in the above table Year 2009 2008 2000 2001 2009 2010 2009 2009 2000 b Give the name of the field that should be chosen as the key field jaguar c Explain why the field to have chosen for your answer to part(b) should be chosen as the key field because other things in Makes column are cars but only Jaguar is an animal. d How many records are there in the table 7 2 Most schools now use databases to store details about each pupil. The table shows some of the field names and data types stored in one pupil database. Field name Data Type Unique Pupil Number Number Firstname Text/Alphanumeric Surname Text/Alphanumeric First Line Address Text/Alphanumeric Second Line Address Text/Alphanumeric Postcode Landline No Text/Alphanumeric Data Of Birth Date FreeSchoolMeals(Y/N) Logical/Boolean a Give the most appropriate data types for the following fields: 1. Firstname Text/Alphanumeric 2. Postcode numberic/Alphanumeric 3. FreeSchoolMeals(Y/N) Logical/Boolean b Give the names of three other fields that are likely to be used in this database Sex, Age, Grade. c Explain which field is used as the key field in the database and why such a field is necessary. UniquePupilNumber. Because it is the only unique things that will not be use for two pupils. d It is important that the data contained in this database is accurate. Describe how two different errors could occur when data is entered into this database. Transcription Errors - where data copied from forms is misread. Transposition Errors - where digits are incorrectly reversed when being entered into da database e explain how the errors you have mentioned in part(d) could be detected or prevented. you can fix transcription errors by verifying data after you enter it. 3 a Explain what is meant by a flat-file database flat-file databases are of limited use and are only suitable for very simple databases b Explain what is meant by a relational database. data is stored in several tables with links between the tables to enable the data in the separate tables to be combined together if needed. c Describe an application where a flat-file database would be suitable. use to simple data storage and retrieval systems such as storing a list of names, addresses, phone numbers. 4 Databases are of two types: flat file and relational a Describe two differences between a flat-file database and a relational database. relational database is more safety and all connect together easy to see and understand, flat-file is more faster b A dress hire company needs to store details of dresses, customers, and rentals. They want to store these details in a database. Which type of database do you suggest and give two reasons for your answer Relational database. because flat-file database it only for simple data, but this company needs to put in details. because it is dress company so the things like dresses, customers and rentals is linked together, relational database is the kind of database that all tables connected, indeed it can unconnected too.