Query Data

Once you have fetched data for an app, either as an aggregate or an SQL element, you can view and display returned records by using database queries or custom SQL queries.

The articles in this section give examples about how to use filters, sorting, calculating aggregated data, and other operations to manipulate your data sets according to your business needs.

Articles in this Section

• Fetch and display data from the database in OutSystems

  Fetching data from the database using Aggregates.

• Filter Query Results

  When designing queries, you can add conditions to filter sets of records returned by aggregates to choose the database content you want to display.

• Sort Results in an Aggregate

  Use fixed and dynamic sorting in Aggregates to display records on your application screens following a customized sorting the records they return.

• Calculate Values from Grouped Data

  Use aggregate functions to calculate values based on groups of identical data.

• Aggregate a Column into a Single Value

  Use aggregate functions on a column to calculate a single value.

• Implement asynchronous data fetching using Aggregates

  Use Aggregates with Fetch properties set to On Start and Only on demand, to implement asynchronous calls to the database. This creates a fast UI.

• Create a Calculated Attribute in an Aggregate

  How to create a new attribute to a data query and base its value on the other record's attributes.

• Get Distinct Values from the Database

  Use an aggregate with grouped columns to obtain only the distinct values of entity attributes.

• SQL Queries

  Use the SQL element to write and execute custom SQL queries.