Logic API

Queries

Build read-only endpoints that return one record, a full list, or pages of records, with inputs and access control.

A query is a read-only endpoint in a module. It runs a Dataverse query, with the filters, columns and related tables you choose, and returns the matching records to the caller. Use queries for lists and searches, such as “the open cases of a customer” or “active products in a price list”.

Add a query

In the tree, open the module and select Queries > Add query.
Enter the Query Name. It becomes the last segment of the address: query openCases in module Service is called at GET /service/opencases.
Choose the Multiplicity (see below).
Define the query with the Query Builder, or switch to FetchXML and paste a FetchXML query.
Add a Query Argument for each value callers pass in, and use the arguments in the query’s conditions.
Set Access Control. See Access control.
Save with Ctrl+S.

Settings

Setting	What it does	Notes
Query Name	Names the query and its address.	3–50 letters and numbers, starting with a letter. The address is lowercase.
Multiplicity	How many records the query returns, and in what shape.	Single, All or Sliced.
Query Builder / FetchXML	The table, columns, filters, sort order and related tables.	Build it visually, or use FetchXML you already have.
Query Argument	Inputs callers pass on the query string.	Each has an Argument Name and a Type; date and time arguments also have a DateTime Behavior, and choice arguments an Option Set.
Access Control	Who may run the query, and when.	Same options as for actions.

Multiplicity

Multiplicity	Returns	When nothing matches	Use it for
Single	One record	`204 No Content`	“My profile”, “the account with this number”
All	Every matching record, as a list	`200 OK` with an empty list	Short, bounded lists: team members, the statuses of a process
Sliced	One page of records, with paging information	`200 OK` with an empty page	Anything that can grow: searches, customer lists, case histories

Sliced queries accept three extra query-string parameters: page, page-size and cursor. See Calling the API.

How it behaves

Queries are always GET requests. Arguments are passed on the query string, for example ?customerId=…&priority=1.
An argument that is missing or of the wrong type returns ARGUMENT_VALIDATION_ERROR.
Callers see whatever the query returns. Use query conditions and user properties to limit callers to their own data. For example, filter cases by the signed-in contact.
Use All only when the number of results is naturally small. For anything that can grow, use Sliced, so callers never load thousands of records at once.

Example: open cases of a customer, page by page

A service portal shows a customer’s open cases, newest first, 20 at a time.

Setting	Value
Module / Query Name	`Service` / `openCases` → `GET /service/opencases`
Multiplicity	Sliced
Query	Table `incident`; columns `ticketnumber`, `title`, `prioritycode`, `createdon`; condition: status is Active and customer equals the `customerId` argument; sort by `createdon` descending
Query Argument	`customerId` (Unique Identifier)
Access Control	Demand Authenticated User

GET /service/opencases?customerId=6b1f0c3e-2d4a-4b5c-8e9f-0a1b2c3d4e5f&page=1&page-size=20
Authorization: Bearer eyJ0eXAiOi...

{
  "cursor": "…",
  "count": 20,
  "totalRecordCount": 47,
  "hasMoreRecords": true,
  "data": [
    { "ticketnumber": "CAS-01842-K9T2", "title": "Router drops connection", "prioritycode": 1, "createdon": "2026-10-21T08:14:00Z" },
    { "ticketnumber": "CAS-01839-R3M7", "title": "Invoice shows wrong VAT rate", "prioritycode": 2, "createdon": "2026-10-20T15:02:00Z" }
  ]
}