# Data Sources Overview
To give Portal access to data in Portal's internal database or external database, create a Data Source. Data Sources are used for many advanced use cases in Portal. Some examples include: custom filter values, dynamically displaying Portal objects based on logged in user, Data Table blocks.
Data Sources must include the following: - Name - Database Connection - SQL Query
SQL queries are often written to include all data from a table. For example: `SELECT * FROM table`