Data-items: The term data item is the word for what has traditionally been called the field in data processing and is the smallest unit of data that has meaning to its users. The phrase data element or elementary item is also sometimes used. Although the data item may be treated as a molecule of the database, data items are grouped together to form aggregates described by various names. For example, the data recurred is used to refer to a group of data items and a program usually reads or writes the whole records. The data items could occasionally be further broken down into what may be called an automatic level for processing purposes. For example, a data item such as a date would be a composite value comprising the day, date and year. But for doing date arithmetic these may have to be first separated before the calculations are performed. Similarly an identification number may be a data item but it may contain further information embedded in it. For example, the IGNOU uses a 9 digit enrollment number. The first 2 digits of these numbers reflect the year of admission, the next 2 digits refer KI the Regional Centre where the student has first opted for admission, the next 4 digits are simple sequence numbers and the last digit is a check digit. For purposes of processing, it may sometimes be necessary to split the data item.
Standardization of data items can become a fairly serious problem in a large corporate with several divisions or plans. ‘Each such unit tends to have its own ways of referring to the data items related to personal accounting, engineering, sales, production, purchase activities, etc. It would be extremely desirable if at the stage of adopting the database approach a commitment from the top management is acquired for prospective standardization across the enterprise for schemas of the data items. 
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