Data Sources
What is a data source?
A data source, in the context of computer science and computer applications, is the location where data that is being used come from. In a database management system, the primary data source is the database, which can be located in a disk or a remote server. The data source for a computer program can be a file, a data sheet, a spreadsheet, an XML file or even hard-coded data within the program.
Explaining data sources
Data sources can differ according to the application or the field in question. Computer applications can have multiple data sources defined, depending on their purpose or function. Applications such as relational database management systems and even websites use databases as primary data sources. Hardware such as input devices and sensors use the environment as the primary data source.
A good example is a temperature and pressure control system for a fluid circulation system such as the ones used in factories and oil refineries, which take all related data from the environment or whatever they are monitoring; so the data source here is the environment. Data such as temperature and pressure of the fluid are taken by sensors regularly and then stored in a database, which then becomes the primary data source for another computer application that manipulates and presents this data.
A data source is most commonly used in context with databases and database management systems or any system that primarily deals with data, and is referred to as a data source name (DSN), which is defined in the application so that it can find the location of the data. It simply means what the words mean: where data is coming from.
Connecting your data sources
A data source is a specific instance of a connection to your data. Data sources provide the structure (schema) of the fields you or other report editors can use to create your reports. Data sources also provide a number of other important functions:
Data sources provide access control to the data via credentials.
Data sources give you a way to model your data, for example, by creating calculated fields, adding parameters, and adjusting data types.
Data sources can provide a consistent definition for the metrics and dimensions that are shared across your business.
Data sources are where you can set other options, such as data freshness and email filters.
When you create a new data report , you either add an existing data source, or create and add a new one. You can add as many data sources, of any type, to a report, as needed.
Data sources and connectors
Data sources use connectors to fetch your data from a specific platform, system, or product.
How (and when) data sources fetch your data
Most data sources maintain a live connection to your data. Your data remains in the underlying data set and is not imported into the portal.
However, for better performance, your data may be stored temporarily in an in-memory cache. Some data source connections let you adjust how often the cache is refreshed. For even faster performance, you can use an extracted data source. The Extract data connector creates a static snapshot of your data. The extracted data is stored securely in the portal, and you can update the snapshot whenever you want.
File upload data sources let you import CSV data into Data Studio. Using a file upload data source, you can visualize information not otherwise supported by the other connectors. File upload data sources behave in many ways like extracted data sources, except you can’t update them automatically. You must import new data manually.
Embedded vs. reusable data sources
Data sources can be either embedded or reusable. Reports can include both embedded and reusable data sources. Data sources you create while editing a report are embedded in the report. To edit an embedded data source, you do so within that report.
Embedded data sources make collaborating on reports and data sources easier. Anyone who can edit the report can also edit the data source. Data sources are reusable. You can reuse these data sources in different reports. Reusable data sources let you create and share a consistent data model across your organization.
Share and copy data sources
When you share or copy a report, all of its embedded data sources are shared or copied along with it. You don’t need to share embedded data sources separately from the report. This means that other report editors can modify the data source.
Reusable data sources aren’t copied or shared when you copy or share a report. If you want someone else to be able to modify a reusable data source, then you must share it with them explicitly.
Note that you don’t need to share a reusable data source in order for viewers of the report to see the data, or for editors to use the fields provided by the data source to create charts and controls in the report.
