8 Flat Files as Sources or Targets. Autodesk inventor professional 2012 32 bits. Each time you use the Import Metadata Wizard to sample data from existing flat files. A flat file database is a database stored as an ordinary unstructured file. Flat files are used not only as data storage tools in database and content. Flat File Format ExampleWhat Is a Flat File Database? If you ask some database administrators (DBAs) about flat file databases, they may wonder if you just told them the world was flat. That's because flat file databases can become unwieldy and complicated. However, they have a use and a purpose, as will be detailed in this lesson. A flat file database is basically a giant collection of data in which the tables and records have no relation between any other tables. In fact, one could have a single table (e.g., My Small Business Data) with everything stored in it, from customers to sales to orders to invoices. Sound too messy? But there are uses. One doesn't necessarily have to normalize a database. By normalize, we mean break out all the repeating values in tables and save them into other, related tables. Sometimes simple is best. In fact, if the data set is fairly simple, the flat file option makes more sense. A CD collection, a list of cell phone numbers, or results from a 10k could be stored in a flat file database. Even a web page or computer program could be written to interact with these types of databases; in fact, from a developer's perspective, it would be easy to maintain. Flat File Database Examples If you have ever created an Excel spreadsheet, you have created a basic flat file! A workbook with multiple tabs makes up the database of the flat-file database; there could be many values that are the same in both worksheets, but they are not linked together. The database table (yes, it is just a snippet from Excel) shown in the image below could be used in a small web application for a running a club: Flat File Example You will notice that some names repeat; for a small table this is not that big of a deal. However, if you wanted to change the record for Dave and add a last name, you have to find all records for him and update each one. This lesson's author, when starting a career in information technology, was given the task of creating a database to track all printers for a given department. He generated an overly complex relational database with over 25 tables. When presented to a colleague, the colleague replied: 'Why not just make a flat file?' This turned out to be the simplest solution; although it was a large file, it wasn't unwieldy and was user-friendly. Using Microsoft Access, a simple user form was created, and no special coding or updates to related tables were needed. When I was heavy into FSX, Aerosoft was the go too place fro Euro airports. Hamburg eddh aerosoft launcher. Relational databases use primary and foreign keys to index the data. A flat file database table can still use an index; however, it's specific only to that table. An index is usually an auto-generated number that identifies the record number in the table, usually starting at 1. The small flat database table below has an index: Example of a Flat File Database Table Even though flat file databases don't have relationships between the tables within them, the tables should still contain an index, which aids in searching and organizing. Although you can create a flat file database in Excel or Microsoft Access, there are a few software applications that were built specifically on the flat file structure: FileMaker or FileMaker Pro, which the author of this lesson used for several web applications; Berkeley DB; and Borland Reflex. Flat File Database Drawbacks Data repeats itself in flat file databases. For example, in the task of tracking department printers, there may be multiple rows for each computer: each computer may connect to multiple printers. If an item on a printer changes, one would have to find all instances of that printer and update each one individually. Of course, it would make sense to only have one row per printer, but flat file databases do not enforce such rules on data entry. Because of the large amount of data that's possible in a flat file database, querying the database can take a long time. Lesson Summary Let's review. This lesson has covered the concept and definition of a flat file database, which is basically a giant collection of data in which the tables and records have no relation between any other tables. ![]() This is unlike normalizing a database, which means to break out all the repeating values in tables and save them into other related tables. Although relational databases are much more robust and allow for stronger data integrity, a flat file database can still have practical use. For simple projects, tables with low record counts, or small databases needed for a web application, the flat file approach can work. However, data can repeat itself in these databases, so maintenance can get tricky if they grow in size and complexity. This is due to a flat file database using an index, which is an auto-generated number that identifies the record number in the table, usually starting at 1. Examples of software that can create flat file databases include Microsoft Excel, Microsoft Access, FileMaker or FileMaker Pro, Berkeley DB, and Borland Reflex.
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