extract particular value from list record column in power query

Hi vijaykaali811 

To get a specific item from a list without expanding it, you can use access the position of an item - which always begins at zero. Assuming List of Records is the name of the list column, you can create a custom column with this formula

[List of Records]{0} // This retrieves the first record from the "List of Records" column

[List of Records]{0}[OS] // This accesses the value associated with the "OS" key in the first record of the "List of Records" column

Sample query:

let
    Source =
        Table.FromRecords({
            [ID = 1, List of Records = { [OS = "rhel"], [version = "rhel8"], [Arch = "x86_64"] }],
            [ID = 2,  List of Records = { [OS = "ubuntu"], [version = "20.04"], [Arch = "arm64"] }],
            [ID = 3,  List of Records = { [OS = "centos"], [version = "7"], [Arch = "x86_64"] }]
        }),
    #"Added Custom" = Table.AddColumn(Source, "OS", each [List of Records]{0}[OS]),
    OS = #"Added Custom"{1}[OS]
in
    OS