An appropriate data type - is attached to the field name in a database, In total there are - 11 data types, Text means - text and data that is a mix of text and numbers e.g. postcode, Number means - numeric data that requires a mathematical calculation, Date/Time - Stores a date or time, Currency - Monetary value such as item price and includes 2 decimal places, Autonumber - Automatically stores a numeric value that is one greater than that in the last record added, Yes/No is also called - Boolean, Yes/No - used to store data that has only two possible values such as yes or no, true or false, and on or off., OLE object - contains an object created by another software package e.g. Excel workbook, Hyperlink - An address that links to another location, such as a website (URL), email address or an external file., Attachment - Files attached to a record, e.g. digital image, Calculated - For the result of a calculation produced from another field in the record, Lookup Wizard - creates a list of values and allows user to select a value from the list and enter into the field, Data validation is - the process of verifying that a program's input data is within the expected range, Data validation guarantees that data is - present, the correct type, range or length, Data that doesn't conform to specified rules - is rejected, The data validation checks are - presence, length, type, format and range, If data is rejected - an error message is displayed and a reason given, A presence check ensures - data is present and does not allow a space to be left blank, Presence checks are mainly used in - online forms, Validation rule for presence requires - "Required" set to "Yes" for the field required, A length check ensures - data entered is the correct number of characters, An example of using length check is - a customer number must contain 6 characters, A type check is used to ensure - data entered is of the correct type, There are several "types" including - numeric, text and date, A format check ensures data entered - matches a predetermined pattern, An example of format check is - a postcode which would have a pattern such as BTXX XXX, A range check ensures data entered - is within a lower and upper limit e.g. between 1-10, Logical operators - compare a value against another e.g. less than (<), less than or equal to (<=), greater than (>) etc,

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