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Maestro user guide

Last updated May 6, 2026

Data Fabric operations in Maestro

Maestro processes can query and update Data Fabric records directly from BPMN task expressions and output mappings. This page documents the supported query prefixes and output actions.

Query prefixes

A query prefix in a Data Fabric expression retrieves records by field value instead of by internal record ID. Two prefixes are supported:

PrefixFull nameReturn typeNo-match behaviorMultiple-match behavior
qes:Query Expansion SingleSingle recordReturns an empty resultReturns an error
qem:Query Expansion MultipleArray of up to 1,000 recordsReturns an empty arrayReturns all matching records

Expression syntax

datafabric.EntityName["qes:FieldName=Value"].FieldToRead
datafabric.EntityName["qem:FieldName=Value"]
datafabric.EntityName["qes:FieldName=Value"].FieldToRead
datafabric.EntityName["qem:FieldName=Value"]

Example — single record lookup:

datafabric.LoanApplicationCase["qes:CaseId=HL-999"].LoanAmount
datafabric.LoanApplicationCase["qes:CaseId=HL-999"].LoanAmount

Example — multiple record lookup:

datafabric.LoanApplicationCase["qem:Status=Pending"]
datafabric.LoanApplicationCase["qem:Status=Pending"]

When to use each prefix

qes: is suited for lookups where exactly one record is expected. When the query matches more than one record, Maestro returns an error and the workflow stops. When no record is found, Maestro returns an empty result and continues execution.

qem: is suited for queries that may return more than one record. Maestro returns an array of up to 1,000 matching records. A process can iterate over the array using a multi-instance marker or a loop, enabling fan-out patterns across multiple Data Fabric records in a single step.

Note:

When migrating expressions from qes: to qem:, update downstream variable references. qes: returns a single record object; qem: returns an array.

Output actions

BPMN task outputs that target a Data Fabric entity support three actions. The action determines whether the output inserts a new record, modifies an existing one, or does both depending on whether a matching record exists.

ActionBehaviorRecord must exist
createInserts a new recordNo
updateModifies an existing record identified by record IDYes
upsertInserts a new record if no match is found; updates the existing record if a match is foundNo

The output action is configured in the Output section of the task properties panel. For more information about the properties panel, see Configuring properties and data.

  • Query prefixes
  • Expression syntax
  • When to use each prefix
  • Output actions
  • Related pages

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