What is the function of coalesce in SAQL?

The function of coalesce in SAQL (Salesforce Analytics Query Language) is to provide a default value when two data streams are combined. This function is particularly useful in scenarios where you might encounter null values within your data. When coalesce is called upon, it examines the provided data streams and returns the first non-null value it encounters. If all values are null, it can return a specified default value, ensuring that your analysis can proceed without missing data points or errors due to null values.

This capability is essential for maintaining data integrity and accuracy in reports and analyses, as it prevents gaps in your data from skewing results. By effectively handling null values with coalesce, you can enhance the robustness of your analytics solutions.