---
name: sigma-data-models
description: >-
  Create, retrieve, or modify a Sigma data model spec (the JSON/YAML
  semantic-layer definition with sources, columns, metrics, relationships,
  filters, controls, folder groupings, and column-level security) by calling
  the Sigma REST API directly. Use when the user wants to author a new data
  model from a description, export/inspect/download an existing model's spec,
  edit columns or metrics, change a model's source, add relationships or
  row-level filters, or otherwise round-trip a data model through code.
  Requires an SIGMA_API_TOKEN — obtain via the sigma-api skill first.
---

# Sigma Data Models (Create / Get / Update)

Round-trip a Sigma data model spec — the JSON definition of pages, sources, columns, metrics, relationships, filters, controls, folder groupings, and column-level security — through the Sigma REST API.

**Auth:** Authenticate via the `sigma-api` skill first to set `$SIGMA_BASE_URL` and `$SIGMA_API_TOKEN`. This skill assumes both are already exported.

**Requirements:** `curl`, `jq`, `base64`. Your Sigma API credentials must have permission to create or edit data models, plus "Can edit" access on the destination folder (for create) or the existing data model (for update). If a request returns 403, ask your Sigma admin to confirm the credential's permissions.

## Reference Index

Feature-specific JSON patterns live in `reference/`. Load each file when you identify the corresponding feature in the user's request — don't read every file up-front.

| File | When to load |
|------|--------------|
| `reference/columns.md` | Calculated columns, formula columns, derived columns; **renaming a column, changing a formula**, warehouse-column ID conventions, column reference rules. |
| `reference/metrics.md` | Metrics, aggregate measures, metric timelines, time-series / trend metrics; **adding a metric to an existing table or changing aggregation**. |
| `reference/relationships.md` | Relationships, foreign-key linking, related tables, cross-table lookups; **adding a relationship between an existing element and a new one** (mixed-ID rule — see `workflows/crud.md`). |
| `reference/sources.md` | Custom SQL sources, join sources, union sources, transpose sources; **swapping a model's source kind** on an existing model. |
| `reference/filters.md` | Row filters, where clauses, date range filters, top-N; **adding/removing a filter on an existing model**. |
| `reference/folders-groupings.md` | Folders, column groupings, column ordering, sort, organize columns; **reordering existing columns**. |
| `reference/column-level-security.md` | Column-level security (CLS), data masking, restrict columns by team / user attribute; **applying CLS to an existing column**. |
| `reference/controls.md` | List/dropdown, text input, text area, number input, number range, date, date range, slider, range slider, segmented, switch, checkbox, top-N controls; **adding a control to an existing page**. |
| `reference/formatting.md` | Column or metric formatting — currency, percentage, date format, decimals, datetime; **reformatting a column or metric on an existing model**. |

## Workflows Index

| File | When to load |
|------|--------------|
| `reference/workflows/crud.md` | Authoring a new model, retrieving an existing model's spec, or modifying / editing / adding to / changing the source of an existing model. Always load before any POST / GET / PUT against `/v2/dataModels` endpoints. Contains the ID-semantics contrast table (CREATE remap vs GET source-of-truth vs UPDATE preserve), full step-by-step CREATE / GET / UPDATE recipes, and the mixed-ID rule for relationships in updates. |

## ID Conventions

Cross-cutting rules. Per-workflow ID semantics (remap vs preserve vs mixed cross-references) live in `reference/workflows/crud.md`.

- Short alphanumeric IDs for generated entities: `"page-1"`, `"table-orders"`, `"col-revenue"`.
- Warehouse column IDs follow `"inode-<tableId>/<COLUMN_NAME>"` — use `"<YOUR_TABLE_INODE>/<COL_NAME>"` as a placeholder.
- Control `id` is the element ID; `controlId` is the formula reference name — keep them distinct.

## Unsupported Features

Call out any of these before presenting the final spec:

- Multiple tables with identical names in the same data model
- Input tables, Python elements, and UI elements
- Referencing Sigma elements in custom SQL
- Partial updates — the create and update endpoints both require the full representation