![]() ![]() There is not much we can do with such a simple database. We could also write:ġ-Amy-Blues/2-Bob-Reds/3-Chuck-Blues/4-Dick-Blues/5-Ethel-Reds/6-Fred-Blues/7-Gilly-Blues/8-Hank-Reds/ which is "comma-separated" ( CSV) format. Other ways to implement the same database are: Today, the same effect is achieved by delimiting fields with a tab character records are delimited by a newline. ![]() This is a very primitive and brittle implementation, dating back to the days of punch cards. In this implementation, fields can be detected by the fact that they all "line up": each datum uses up the same number of characters as all other data in the same column extra spaces are added to make them all the same length. Some databases omit this, in which case the question is left open: "What is in these fields?" The answer must be supplied elsewhere. The first line is not a record at all, but a row of "field labels" - names that identify the contents of the fields which they head. (Sometimes, although this is not strictly correct, the word "field" refers to just one datum within the file - the intersection of a field and a record.) Bob's id is "2" his name is "Bob" (no surprise!) and his team is the "Reds". These columns are called "fields".Īlso note that all the information in, say, the third line from the top "belongs to" one person: Bob. All these team designations are found in the third column only. We have decided Pico users will gang up into teams, and some belong to the Reds and some to the Blues. Likewise, the data in the second column is "all the same" - names. Note that the data in the first column is "all the same" - that is, they are all id numbers (serial numbers). The data - the information itself - has simply been written out in table form: ![]() The simplest implementation of Pico is shown below, inline in this text. Let us explore an example database that stores the users of an imaginary miniature version of Wikipedia, "Pico". These types of database are so common that we often see one without thinking of it as a database at all. Another example is a simple HTML table, consisting of rows and columns. The classic example of a flat file database is a basic name-and-address list, where the database consists of a small, fixed number of fields: Name, Address, and Phone Number. ![]()
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