What Is a Data Source?

Any file that contains data is considered a data source

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A data source (sometimes called a data file) is just as simple as it sounds: a place where data is being taken from. The source can be any kind of data of any file format, so long as the program understands how to read it. 

Various applications can use a data source, including database applications like Microsoft Access, MS Excel and other spreadsheet programs, word processors like Microsoft Word, your web browser, offline programs, etc. A common scenario when it comes to Microsoft Word using a data source is for Word to make a mail merge from data taken from an Excel document. See our introduction to mail merge for more information.

Important Data Source Facts

A data source file used in one program for one purpose, might not have any relevance in a different program even if they both use data source files. In other words, a particular "data source" is subjective to the program using the data.

For example, a data source for a mail merge in Microsoft Word might be a CSV file that holds a bunch of contacts so that they can be automatically written to a Word document for printing envelopes with the right names and addresses. Such a data source, however, isn't very useful in any other context.

Data Source Examples

As mentioned above, a data source also called a data file, is simply a collection of records that store data. It's this data that's used to populate merge fields in mail merges. This is why any text file can be used as a data source, be it a plain text file or an actual database file.

They can come from programs like MS Access, FileMaker Pro, etc. In theory, any Open Database Connectivity (ODBC) database can be used as a data source. They can also be created in spreadsheets from Excel, Quattro Pro, or any other similar program. The data source can even be a simple table in a word processor document.

The idea is that a data source can be any kind of document so long as it's organized to provide structure for the receiving program to pull data from. For example, an address book contact can be used in some scenarios because there's a column for a name, address, email account, etc.

Another kind of data source might be a file that records the times that people check in to a doctor's office. A program can use the data source to aggregate all the check-in times and display them on a website or use them within a program, either for displaying the content or having it interact with some other kind of data source.

Other kinds of data sources might be taken from a live feed. The iTunes program, for instance, can use a live feed to play internet radio stations. The feed is the data source and the iTunes application is what displays it.