Flow Designer variables can store record data and complex data using the following data types:
Integer: A whole number that can be used in mathematical operations.
Array: A collection of items that can be accessed by their index or iterated over using a For each action.
String: Any kind of text, such as email addresses or the text contents of a file.
Reference:
Define and Use Data Types in a Flow (Flow Designer)
Variable data types - Power Automate | Microsoft Learn
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