Variables

Steps pass values to each other through variables. Some variables you declare yourself with New Variable. Many more appear on their own: almost every step publishes its result under its own name, so a later step can use GetCase.title or DiscountCheck.Output.Discount without any extra work. In expressions, you pick all of them from the expression editor, next to the flow’s inputs and Data items.

Kinds of variables

Kind	Where it comes from	Example	Visible to
Declared variable	A New Variable step. Its name is the step name.	Total, FollowUp	Every step after it
Step result	Steps that read or create something publish it under the step name.	GetCase, OpenOpps.Output.value	Every step after it
Loop variable	Loop, Iterator and Try / Catch publish values for the steps inside them.	EachContact.Item, SyncTry.Error	Only the steps inside that step

Inputs and Data items are available to every step too. They appear in the expression editor alongside the variables.

Step results

Each step’s variables are named after the step, so give steps short, meaningful names. The list below covers every step that publishes variables.

Step	Variables	Holds
Get Entity By Id	<Step>	One row with the chosen columns; empty when no row has that id
Get Entities By Relationship	<Step> Entities	List of related rows
Execute Query	<Step>	One row (Single), a list of rows (All) or one page of rows (Sliced)
Aggregate Query	<Step>.Output.value	The count, sum, average, minimum or maximum
Update / Delete Records from Query	<Step>.Output.recordCount	Number of rows changed or deleted
Clone Record	<Step>.Output.recordId	Lookup to the copy
Queue (Add to queue)	<Step>.Output.queueItemId	Lookup to the new queue item
Create Email	<Step>.Output.emailId	Lookup to the email
Resolve Recipients	<Step>.Output.users	List of user lookups
Run Logic Block, Run Logic Flow, Run Process Action, Execute SDK Message	<Step>.Output.<name>	One variable per output
Loop	<Step>.Counter, <Step>.Start, <Step>.Count	Current counter value and the bounds
Iterator	<Step>.Item, <Step>.Index	Current item and its position (starting at 1)
Try / Catch	<Step>.Error	The error message (Text), inside Catch only
Call Rest Api	[<Step>][Request], [<Step>][Response][<code>], Response Text, [<Step>][error]	Request body, parsed response per status code, raw response text, call error

Steps that change data without returning anything new (Save Entity, Assign Record, Set State / Status, Recalculate Rollup and others) publish no variables. Save Entity writes the new id back into the row variable you saved.

Declare a variable

Add a New Variable step. The step name becomes the variable name, and you choose a Type:

Type (Dataverse)	On-premises label	Holds
Yes/No	Two Options	Yes or No
Date and Time	Date and Time	A date and time, with a behavior: Date Only, Time Zone Independent or User Local
Decimal Number	Decimal Number	An exact decimal
Floating Point Number	Floating Point Number	An approximate number
Currency	Currency	A money amount
Whole Number	Whole Number	An integer
Text	Text	Text
Row	Entity	A row of the table you choose
Lookup	Lookup	A reference to a row of the table you choose
Choice	Option Set	One option of the choice you choose
Template Definition	Template Definition	One row shaped by a template from the Templates tab
Object	Object	An object; offered only when objects are defined

Once the type is complete, choose one value or List of values. A line under the type says what the variable holds, for example “Holds a list of Contact rows.”

No initial value

New Variable has no initial-value field. The variable starts empty; a Row variable starts as a new, unsaved row of its table. Give it a value with Update Variable in the next step.

Dynamics 365 CE on-premisesType labelsApplies to the other edition

On-premises shows Two Options, Entity and Option Set where Dataverse shows Yes/No, Row and Choice.

Change a variable

Use Update Variable. Pick the Variable (fixed once saved), then:

• for a Row or Object variable, add one line per field, each with an operator and a value;
• for any other variable, set its Value: an operator plus an expression.

Operator	What it does
Set	Replaces the value (or the field’s value) with the expression’s result.
Set to Nothing	Clears the value.
Add Item To Collection	Adds an item to a list variable.
Remove Item From Collection	Removes an item from a list variable.

Step results such as a row read with Get Entity By Id are variables too, so you can change fields of a row you read and save it back with Save Entity.

Update a variable from inside a branch, loop or Try

A variable declared earlier in the flow can be updated from anywhere after it: inside a Condition branch, a switch case, a Loop or Iterator, or a Try, Catch or Finally branch. The change is visible after the step that contains it. This is how you keep a running total or collect items across loop iterations.

Work with lists

• Collect items: declare a list variable (for example a Lookup to Contact with List of values) and use Add Item To Collection inside an Iterator.
• Use a list: pass it to Iterator’s Collection, to Associate Multiple Relationship’s Entities, to Create Email’s To, or to list functions such as Collection Count, Filter and Projection.
• Build rows in bulk: collect Row variables in a list, then create them all at once with Execute Multiple Request.

Examples

Running total. Add up the value of an account’s open opportunities while you loop through them:

1. New Variable PipelineTotal, type Currency.
2. Iterator EachOpp over OpenOpps (an Execute Query with Multiplicity All).
3. Inside the Iterator, Update Variable PipelineTotal → Set PipelineTotal + EachOpp.Item.estimatedvalue.

For a total like this, an Aggregate Query with Sum is faster, because the sum is calculated by the server without reading the rows. Use the loop when you also need to act on each row.

New row. Create a follow-up task:

1. New Variable FollowUp, type Row (Task).
2. Update Variable FollowUp: Set Subject to Concatenate("Follow up: ", GetCase.title), Regarding to CaseId, Due Date to Add Days(Now, 2).
3. Save Entity with Entity = FollowUp. After the save, FollowUp holds the id of the new task.

Related

• Variables steps
• Data types
• Empty values
• Types