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In the above picture, I’ve defined and typed into the form, fields that I think are appropriate for an address table. Access assigns the
ID field as explained below, when the table is saved for the first time.
Notice the Data Type entries. A tiny arrow head appears at the right end which when opened (by being clicked) shows a list of all the data types available for use in defining fields. They are: Text, Memo, Number, Date/Time, Currency, AutoNumber, Yes/No, and three more you can forget about. They are for advanced users. These names indicate the type of information you intend to store in the fields. If you were going to store money values in a field then you would use the Currency data type. If you intended to store Dates, then you would use Date/Time data type and so on. The names themselves indicate the usage. I used mostly Text and one Memo type. Text is used for characters and numbers in the alphabet up to 255 maximum characters. The Memo type is the same as text except | that it is unlimited.
You could store a whole book in memo fields. With all fields defined, the table design can be closed, saved and given a name.
When the table is saved for the first time, Access will ask if you want it to add a Primary Key field. The answer to this question is always yes. Access will assign a field called ID and will assign the data type AutoNumber. AutoNumber is a field that will increment each time a new row ( i.e., a new record remember?) is added to the table. The user can not change or influence this field. The user can use this field however. For example, if you need a unique identifier, this field can be used as a unique identifier. Say you have three people in your table whose last names are all Smith. The AutoNumber will identify them separately because it will be a different number for each of the Smiths. Next we close the table, by clicking the X in the upper right corner of the window. Then a dialog box will appear asking if you want to save the table. Answer yes and click OK to close the box.
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