Iterator
Introduction
The Iterator icon is not actually an operator. It is just an icon, intended to be used to represent operators for which no dedicated icon is available.
I have so far only seen this icon being used for the Online Index Insert operator. Even when I deliberately try to display an execution plan that uses newer operators (e.g. JSON Index Seek) in an older version of Management Studio, I get an error, not an execution plan with the Iterator icon.
Visual appearance in execution plans
Depending on the tool being used, the Iterator icon is displayed in a graphical execution plan as shown below:
|
SSMS and VS Code |
Legacy SSMS |
Plan Explorer |
Paste The Plan |
 |
 |
 |
(unknown) |
Algorithm
The Iterator icon is not used to represent a specific operator, but could in theory represent any operator for which no suitable icon is available. This might not actually happen in current versions of Management Studio, but that doesn’t mean that it will never happen.
As a result, the Iterator icon can in theory represent many different operators. Each of them has their own algorithm. It is impossible to describe a single algorithm here. To find more information about the specific operator, look at the operator name below the Iterator icon or in the Physical Operation property of the icon, then find that operator in the Operator List.
Operator properties
Iterator is an icon that (in theory) can represent multiple operator represented. Which properties it has depends on the actual operator represented. You can find this information on the page of that operator, which can be found through the Operator List. To find the specific operator represented, the following property (which is common to all operators) can be useful.
| Property name | Description |
|---|---|
| Physical operation | The name of the operator. |
Change log
(Does not include minor changes, such as adding, removing, or changing hyperlinks, correcting typos, and rephrasing for clarity).
September 29, 2026: Added.
