Data and information are vital organizational
resources that must be managed effectively for the benefit of all end users in
an organization.
resources that must be managed effectively for the benefit of all end users in
an organization.
Data are organized into characters, fields,
records, files and database, just as writing can be organized into letters,
words, sentences, paragraph and documents.
records, files and database, just as writing can be organized into letters,
words, sentences, paragraph and documents.
Characters
The character is the most basic logical data
element. It consists of a single alphabetic, numeric or other symbols. Also
character is the most basic element of data that can be observed and
manipulated. A character is the smallest element in a file and can be
alphabetic, numeric or special symbols.
element. It consists of a single alphabetic, numeric or other symbols. Also
character is the most basic element of data that can be observed and
manipulated. A character is the smallest element in a file and can be
alphabetic, numeric or special symbols.
Also, this is the smallest unit of data that can be
processed.
processed.
Types
of Characters
of Characters
There are three (3) types of characters:
a.
Alphabetic Characters: These are the 26 letters of the alphabets i.e. A,
B, C —- Z.
Alphabetic Characters: These are the 26 letters of the alphabets i.e. A,
B, C —- Z.
b.
Numeric Characters: This are digit i.e. 0, 1, 2, 3, 4, 5, 6, 7, 8,
and 9
Numeric Characters: This are digit i.e. 0, 1, 2, 3, 4, 5, 6, 7, 8,
and 9
c.
Special Character: These are the punctuation symbols and arithmetic
signs such as (+) plus, (-) minus, back slash (I) asterisk (*) multiplication
(x) etc.
Special Character: These are the punctuation symbols and arithmetic
signs such as (+) plus, (-) minus, back slash (I) asterisk (*) multiplication
(x) etc.
The combinations of both alphabet and numeric
characters are known as alphanumeric character (e.g. Al, B4, C4, D5, F9)
characters are known as alphanumeric character (e.g. Al, B4, C4, D5, F9)
Fields
This is the next higher level of data. it is a group
of characters that describes particular characteristics of a person, place,
things or events. A field consists of a group of letters e.g. the grouping of
alphabetic characters in a person’s name, forms a name field. Also the grouping
of numeric characters in a patient’s hospital number form hospital number
field.
of characters that describes particular characteristics of a person, place,
things or events. A field consists of a group of letters e.g. the grouping of
alphabetic characters in a person’s name, forms a name field. Also the grouping
of numeric characters in a patient’s hospital number form hospital number
field.
Byte
The unit of measurement is the byte. A byte is the
amount of computer space required to store one character of information. A byte
is made up of bits, a bit is the smallest unit of data. A bit is a binary
digit, i.e. 0 and 1
amount of computer space required to store one character of information. A byte
is made up of bits, a bit is the smallest unit of data. A bit is a binary
digit, i.e. 0 and 1
e.g. 0 — A bit
1 — A bit
11110000 — A byte
An 8 bit character is known as a byte
Conversion
A unit measurement for computer memory asurement
for computer memory.
for computer memory.
8 – bits 1
byte
byte
1000 bytes 1 kilo byte (Kb) = 1024 bytes
1000 Kb mega byte (MB) = 1,048,576 bytes
1000 MB 1 Gigabyte (GB) = 1,073,741,824 bytes
Records
This is the next higher level of data. Related
fields of data are grouped to form a record. So a record represent a collection
of attributes that describes an entity an example is a student course record
which consist of data fields such as students name, registration No, the list
of courses and scores grades. Fixed-length records contain a fixed number fixed
length data field. Sometimes, variable length records are allowed. This
contains a variable number of fields and field lengths.
fields of data are grouped to form a record. So a record represent a collection
of attributes that describes an entity an example is a student course record
which consist of data fields such as students name, registration No, the list
of courses and scores grades. Fixed-length records contain a fixed number fixed
length data field. Sometimes, variable length records are allowed. This
contains a variable number of fields and field lengths.
Record: A record
is made up of number of related fields e.g. a customer record or an employee of
payroll record.
is made up of number of related fields e.g. a customer record or an employee of
payroll record.
