Add custom columns

In DoordaOnline, you can enhance your data analysis by creating custom columns. Custom columns allow you to perform calculations on existing data fields, enabling the derivation of new metrics without altering the underlying database. This guide will walk you through the process of adding custom columns to your questions in DoordaOnline.

What Are Custom Columns?

Custom columns are user-defined fields that perform calculations or transformations on existing data within DoordaOnline. They allow you to create new metrics or dimensions based on the data already available, facilitating more tailored and insightful analyses.

Creating a Custom Column

To add a custom column in DoordaOnline:

1. Start a New Question:

   • Navigate to the New Question option.

   • Select the database and table you wish to query.

2. Access the Custom Column Feature:

   • In the query builder, click on the Custom Column button, typically represented by a + icon next to the list of columns.

3. Define the Custom Column:

   • Name: Provide a descriptive name for your new column.

   • Formula: Enter the expression or calculation for the column. DoordaOnline supports various functions and operators for creating expressions.

4. Validate and Save:

   • Ensure your formula is correctly structured.

   • Click Done to add the custom column to your question.

Example Use Cases

• Calculating Profit Margin:

  • If you have 'Revenue' and 'Cost' columns, create a custom column with the formula:

    ([Revenue] - [Cost]) / [Revenue]
    

    This calculates the profit margin as a percentage.

• Combining Text Fields:

  • Merge 'First Name' and 'Last Name' columns:

    [First Name] || ' ' || [Last Name]
    

    This concatenates the first and last names with a space in between.

• Conditional Logic:

  • Classify sales performance:

    CASE WHEN [Sales] > 10000 THEN 'High' ELSE 'Low' END
    

    This assigns a 'High' or 'Low' label based on sales figures.

Tips for Using Custom Columns

• Test Your Formulas: Always validate your expressions to ensure they return the expected results.

• Use Parentheses for Clarity: Group operations using parentheses to avoid ambiguity.

• Be Mindful of Data Types: Ensure that the operations you perform are compatible with the data types of the fields involved.

By leveraging custom columns in DoordaOnline, you can perform more nuanced analyses and derive insights tailored to your specific needs.