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Metrics SQL

You can write a SQL query referring to metrics definitions and dimensions defined in a metrics view. It should have the following structure:

type: api
metrics_sql: SELECT publisher, domain, total_records FROM ad_bids_metrics

Querying Fundamentals​

Metrics SQL transforms queries that reference dimensions and measures within a metrics view into their corresponding database columns or expressions. This transformation is based on the mappings defined in a metrics view YAML configuration, enabling reuse of dimension or measure definitions. Additionally, any security policies defined in the metrics view are also inherited.

Example: Crafting a Metrics SQL Query​

Consider a metrics view configured as follows:

#metrics/ad_bids_metrics.yaml
type: metrics_view
title: Ad Bids
model: ad_bids
timeseries: timestamp
dimensions:
  - name: publisher
    expression: toUpper(publisher)
  - name: domain
    column: domain
measures:
  - name: total_records
    display_name: Total records
    expression: COUNT(*)

To query this view, a user might write a Metrics SQL query like:

SELECT publisher, domain, total_records FROM ad_bids_metrics

This Metrics SQL is internally translated to a standard SQL query as follows:

SELECT toUpper(publisher) AS publisher, domain AS domain, COUNT(*) AS total_records FROM ad_bids_metrics GROUP BY publisher, domain

Security and Compliance​

Queries executed via Metrics SQL are subject to the security policies and access controls defined in the metrics view YAML configuration, ensuring data security and compliance.

Limitations​

Metrics SQL is specifically designed for querying metrics views and may not support all features found in standard SQL. Its primary focus is on providing an efficient and easy way to extract data within the constraints of metrics view configurations.

Supported SQL Features​

  • SELECT statements with plain dimension and measure references.
  • A single FROM clause referencing a metrics view.
  • WHERE clause that can reference selected dimensions only.
  • Operators in WHERE and HAVING clauses include =, !=, >, >=, <, <=, IN, LIKE, AND, OR, and parentheses for structuring the expression.
  • HAVING clause for filtering on aggregated results, referencing selected dimension and measure names. Supports the same expression capabilities as the WHERE clause.
  • ORDER BY clause for sorting the results.
  • LIMIT and OFFSET clauses for controlling the result set size and pagination.
warning

The Metrics SQL feature is currently evolving. We are dedicated to enhancing the syntax by introducing additional SQL features, while striving to maintain support for existing syntax. However, please be advised that backward compatibility cannot be guaranteed at all times. Additionally, users should be aware that there may be untested edge cases in the current implementation. We appreciate your understanding as we work to refine and improve this feature.

Using Metrics SQL in custom APIs​

To expose Metrics SQL queries as HTTP API endpoints, see the Metrics SQL APIs guide. You can also add dynamic templating, security rules, and OpenAPI documentation to your Metrics SQL APIs.