Methods of validation/methods of verification/file organization/spreadsheet

What is validation?

What is validation?

This is a checking process in a program that is used to find out if the data is genuine.

What is the function of the validation check?

It is used to ensure that the data entered into a database form, web form, or computer program conforms to a set of validation rules or programs.

What are examples of validation checks?

Range check

Presence check

Reasonable check

Data type check

Consistency check

Format check

Length check

What is the function of a range check?

This is used to ensure that the data entered is within a certain range. For example: at an amusement Park the slides in the kid’s section can only be used by children between the ages of 3 and 8

What is the function of the presence check?

This is used to ensure that the data is entered and can be used on any field in a database. For example: all fields that are marked required must be filled out.

What is the function of the reasonable check?

This is used to ensure that the data is reasonable within its context. For example, it is unacceptable for an employee without a driver’s license to be given the rate of driver.

What is the function of the data type check?

This is used to determine whether the data is of the intended data type. For example, a field might only accept numeric data. If a non-numeric character is inserted, the system may reject it because it is not of the intended data type.

What is the function of the consistency check?

This is used to compare the data of two or more fields to make sure that they correctly relate to each other. For example, if a form recorded a response of 6 for the number of children, and 14 for age, at least one of those is probably incorrect

What is the function of the format check?

This is used to ensure that the data conforms to the required format. For example, the data must be entered in the format: day/month/year

What is the function of the length check?

This is used to ensure that the data entered is of the correct length. For example, the year of birth must 4 four digits, e.g. 2020

What is a file?

This is a container in a computer system used to store data, information, or programs.

Define the term file access method

This refers to how data is stored and how files are stored on the storage device.

What are the types or methods of file access?

1. Serial

2. Sequential

3. Random and direct

Define the term serial file access

This is the process of reading in the order that words were written. In other words, it means to start at the beginning and read to the end in one go. For example, to read chapter 3 the day after reading chapters 1 and 2, you’d have to read chapters 1 and 2 again to get to Chapter 3

Define the term sequential file access

This means that the material is required to be ordered in a particular way. For example, if a publisher sequenced the chapter of their book in order, chapter 3 or any other chapter could be accessed more quickly than for serial access.

Define the term binary chop

This is a simple method used to find a chapter in a book by opening it halfway through and seeing which chapter you’re in. As a result, you can then decide if the chapter you want is the first or second half of the book.

What is random and direct file access?

In this file access method, data can be accessed without the need to follow a particular order or sequence, randomly. For example, you can jump straight to the required page/chapter in a book by looking for that page/chapter in the table of contents.

What is backup?

This is the process of copying files to a separate removable storage device so that they can be restored to the original location if they are ever lost or destroyed.

What is system backup?

This is the copying of all files on a computer system that can be used to restore the entire computer in case of hardware failure or data loss.

What is archiving?

This is the act of storing infrequently accessed and modified files on a separate storage device.

What is a real-time system?

This is a computer system in which the response time is critical. For example, self-driving cars have to be real-time systems.

What is verification?

This is the process in which data that has already been input is checked to ensure that it matches the data on the source document.

What are the methods of verification?

Proofreading and double entry

What is double entry?

This is a data verification method in which the data is entered twice by two different data entry clerks and are compared against each other to ensure that they are identical. E.g when you are changing your password and you enter it twice

What is double entry?

This is a manual method of verification in which a data entry clerk visually checks the source document against data that was already input by another data entry clerk.

Which method of verification is quicker but less reliable?

Proofreading is less reliable but significantly quicker than double entry

What are the types of errors?

1. Typographical error

2. Transposition error

What is a typographical error?

This is a type of error that affects the text by such as missing or adding characters

What is a transposition error?

This is a type of error in which the position of 2 adjacent characters in a number or string of text are switched.

What are the methods of file organization?

1. Sequential file organization

2. Serial file organization

3. Direct file organization

4. Random file organization

What is sequential file organization?

In this file organization data is stored in a specific order, using based on a key field. New records are added which makes it easier to read and process data from start to finish. Example a telephone directory

What is serial file organization?

In this file organization, data is stored in the order it is received. It is similar to sequential file organization but does not require a specific order. The data is written consecutively without any sorting. It is best used for transaction logs and error records

What is direct file organization?

In this method, a unique key or address is assigned to each record, enabling direct access to the data without searching through other records, which allows for faster data retrieval. It is best used for customer databases and inventory systems

What is random file organization/ hashed file organization?

This file organization allows records to be stored in a non-sequential manner. It uses a hash function to determine where data will be stored enabling fast access. It is best used in interactive applications like games or multimedia systems.

What is a spreadsheet?

This is a table consisting of cells that hold accounting data and stimulate the traditional spreadsheet.

What is a workbook/spreadsheet?

This is used to organize data in rows and columns and to perform calculations on the data.

What is a workbook/spreadsheet?

This is a spreadsheet file that contains one or more worksheets

What is a worksheet?

This is a single page in a spreadsheet/workbook.

What is a column?

This runs vertically in the grid layout of a worksheet

What is a row?

These run horizontally in the grid layout of a worksheet and are numbered numerically.

What is a cell?

This is where a column and a row intersect in a spreadsheet, and is referenced by its column letter and row number.

What is the function of a cell address?

This is used to identify a single cell in a worksheet and is given in the format A1, where the letter A indicates the column and the number 1 indicates the row.

What is a range?

This is a rectangular block of cells on a worksheet which is referenced by indicating the upper left cell and the lower right cell by placing a colon between the two cell addresses.