Migrate from dbt Semantic Layer

The dbt Semantic Layer already expresses your business in entities, dimensions, measures, and metrics — which maps unusually cleanly onto Malloy. Credible reads your MetricFlow definitions, flattens the measure/metric split into Malloy measures, and — where you connect it — validates each metric against the Semantic Layer's own query engine.

What Credible Reads

Your semantic models (semantic_models: YAML — entities, dimensions, measures) and metrics (metrics: YAML — simple, ratio, derived, cumulative). The agent parses that project YAML directly — the fullest-fidelity input, since the YAML carries expr, filter, and agg_time_dimension details the compiled APIs abstract away. Connecting the official dbt MCP server (get_metrics, get_dimensions, get_entities, execute_sql) or the Semantic Layer APIs (GraphQL / JDBC / Python) is optional and adds live metric validation.

What Comes Across

The everyday modeling carries over. Here's how the bigger pieces land — and where they get better:

The Migration Flow

Credible reads the semantic models and metrics, translates entities to keys/joins and measures/metrics to Malloy measures, enriches with #(doc)/#(index) tags, and — where you connect it — validates by querying each metric through the Semantic Layer API at the same grain and diffing the results — MetricFlow owns SQL generation, so its result is the canonical number to match.

What Credible Handles

• The measure/metric split flattens into one set of Malloy measures. A simple metric is often just a rename of its measure — Credible won't create two Malloy fields where one belongs.
• metric_time and the time spine have no Malloy equivalent. Credible chooses the concrete date field per view and truncates with .month/.day; cumulative metrics are rebuilt as view-level window calculations.
• Derived and ratio metrics reference other metrics, not columns. Credible resolves the dependency chain (metric → metric → measure → column) before writing the Malloy expression.

Before & After

dbt semantic model and metrics:

semantic_models:
  - name: orders
    model: ref('fct_orders')
    defaults:
      agg_time_dimension: order_date
    entities:
      - name: order_id
        type: primary
      - name: customer
        type: foreign
        expr: customer_id
    dimensions:
      - name: order_date
        type: time
        type_params: { time_granularity: day }
      - name: status
        type: categorical
        expr: order_status
    measures:
      - name: order_total
        description: Sum of order amounts
        agg: sum
        expr: amount

metrics:
  - name: revenue
    type: simple
    type_params: { measure: order_total }
  - name: completed_revenue
    type: simple
    type_params: { measure: order_total }
    filter: "{{ Dimension('order__status') }} = 'completed'"
  - name: completion_rate
    type: ratio
    type_params: { numerator: completed_revenue, denominator: revenue }

source: orders is conn.table('analytics.fct_orders') extend {
  primary_key: order_id
  join_one: customers is conn.table('analytics.dim_customers') on customer_id

  dimension:
    #(doc) Order status
    #(index)
    status is order_status

  measure:
    #(doc) Total revenue (USD)
    # currency
    revenue is sum(amount)

    #(doc) Number of orders
    order_count is count(order_id)

    #(doc) Revenue from completed orders
    # currency
    completed_revenue is sum(amount) { where: status = 'completed' }

    #(doc) Share of revenue from completed orders
    # percent
    completion_rate is completed_revenue / revenue

  view:
    #(doc) Revenue by month
    revenue_by_month is {
      group_by: order_date.month
      aggregate: revenue
    }
}

The two simple metrics collapse into their measures rather than duplicating them; completion_rate becomes a straight ratio; and the Jinja filter becomes a { where: … } on the measure.

More than a reformat. Your metrics become directly queryable and composable — not just a metrics API — AI-discoverable through the AI Analytics Engine, and deliverable to every surface. See what you gain →

Next Steps