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INFORMATION AND COMMUNICATION TECHNOLOGY ! PowerPoint Presentation
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INFORMATION AND COMMUNICATION TECHNOLOGY !

INFORMATION AND COMMUNICATION TECHNOLOGY !

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INFORMATION AND COMMUNICATION TECHNOLOGY !

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  1. INFORMATION AND COMMUNICATION TECHNOLOGY ! DATA TYPES … BY: MUHAMMAD UMAIR KHAN, 9B5

  2. WHAT IS DATA ? WHAT ARE THE DIFFERENT TYPES OF DATA ? • RAW FACTS AND FIGURES FOR MANIPULATION ARE KNOWN AS DATA. • AS EACH DATA HAS A DATA TYPE, THERE ARE SIX TYPES OF DATA – • TEXT-IT ONLY CONTAINS DATA THAT IS TYPED IN ALPHABETS. • ALPHANUMERIC-IT CONTAINS DATA THAT IS TYPED IN BOTH ALPHABETS AND NUMBERS. • NUMERIC-IT ONLY CONTAINS DATA THAT IS TYPED IN NUMBERS WHICHIS OF TWO TYPES- 1) INTEGER. 2) REAL. • DATE/TIME-IT CONTAINS OF DIFFERENT FORMATS. E.g.-DD/MM/YY. • CURRENCY-IT CONTAINS DATA WITH CURRENCY SYMBOLS. E.g.- £ • BOOLEAN/LOGICAL-IT CAN HAVE TWO OPTIONS. E.g.-TRUE OR FALSE , YES OR NO.

  3. WHAT ARE THE THREE LOGICAL OPERATORS AND WHAT IS KEY FIELD/PRIMARY KEY ? • THE THREE LOGICAL OPERATORS ARE -OR, AND, NOT. • KEY FIELD/PRIMARY KEY – IT CONTAINS UNIQUE DATA ITEM FOR e.g.– ID NO. IT IS USED TO LOCATE A RECORD IN A FILE DURING A SEARCH OPERATION AND TO CREATE RELATIONSHIPS.

  4. WHAT IS A DATABASE ? • A DATABASE IS AN ORGANISED COLLECTION OF INFORMATION TO ALLOW MANIPULATION AND SEARCHING OF DATA. • FLAT-FILE DATABASE-IT IS A DATABASE THAT ONLY CONTAINS A SINGLE TABLE OF DATA. • RELATIONAL DATABASE- IT CONTAINS TWO OR MORE TABLES OF DATA CONNECTED BY LINKS CALLED RELATIONSHIPS.

  5. WHAT IS FOREIGN KEY ? • IT IS ONE OF THE FIELDS THAT RELATE WITH ANOTHER FIELD AND ACTS AS A PRIMARY KEY IN THE OTHER TABLE OR IT RELATES TABLES IN A DATABASE TO ONE ANOTHER AND ACTS AS A PRIMARY KEY IN THE OTHER TABLE.

  6. DATA VALIDATION AND VERIFICATION. • DATA VALIDATION- CHECKING WHETHER THE DATA IS SENSIBLE (VALID) OR NOT. • PRESENCE CHECK. • RANGE CHECK. • LENGTH CHECK. • TYPE CHECK. • FORMAT CHECK. • DATA VERIFICATION – • PROOF READING- A PERSON COMPARES AND CHECKS IF THERE ARE ANY DIFFERENCES IN THE DOCUMENT THAT IS PRINTED FROM THE ORIGINAL COPY AND CORRECTS IT. • DOUBLE-ENTRY- DATA ENTERED TWICE INTO THE SYSTEM (PREFERABLY BY TWO DIFFERENT PEOPLE) AND VERIFIED BY COMPARING.

  7. THANK YOU!