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john_dawson
Helper I
Helper I

ExpandRecordColumn versus ExpandListColumn

Problem: when expanding a JSON dataset, programmatically, you can expand a list of Tables using Table.ExpandListColumn, specifying only the column name to be expanded, which is fine. But if you want to expand a list of Records, you seem to have to specify the column names manually. It would be preferable, to have a more generic, less fragile, solution, that would allow you request all columns, without needing to name them, or at least to use a function that could return those column names, before expansion, so to speak. Is this possible?

1 ACCEPTED SOLUTION
ImkeF
Community Champion
Community Champion

Hi @john_dawson,

 

you can use this function instead:

 

(Table as table, ColumnName as text) =>
Table.ExpandRecordColumn(Table, ColumnName, Record.FieldNames(Table.Column(Table, ColumnName){0}))

It automatically expands all fields of the records that are found in the first rows record.

 

If the records are different and the names of all records within that column have to be taken into account, you can use this function instead:

 

 

= (Table as table, ColumnName as text) =>
Table.ExpandRecordColumn(Table, ColumnName, Record.FieldNames(Record.Combine(Table.Column(Table, ColumnName))))

might be a bit slower then

Imke Feldmann (The BIccountant)

If you liked my solution, please give it a thumbs up. And if I did answer your question, please mark this post as a solution. Thanks!

How to integrate M-code into your solution -- How to get your questions answered quickly -- How to provide sample data -- Check out more PBI- learning resources here -- Performance Tipps for M-queries

View solution in original post

3 REPLIES 3
ImkeF
Community Champion
Community Champion

Hi @john_dawson,

 

you can use this function instead:

 

(Table as table, ColumnName as text) =>
Table.ExpandRecordColumn(Table, ColumnName, Record.FieldNames(Table.Column(Table, ColumnName){0}))

It automatically expands all fields of the records that are found in the first rows record.

 

If the records are different and the names of all records within that column have to be taken into account, you can use this function instead:

 

 

= (Table as table, ColumnName as text) =>
Table.ExpandRecordColumn(Table, ColumnName, Record.FieldNames(Record.Combine(Table.Column(Table, ColumnName))))

might be a bit slower then

Imke Feldmann (The BIccountant)

If you liked my solution, please give it a thumbs up. And if I did answer your question, please mark this post as a solution. Thanks!

How to integrate M-code into your solution -- How to get your questions answered quickly -- How to provide sample data -- Check out more PBI- learning resources here -- Performance Tipps for M-queries

Anonymous
Not applicable

Woo-hoo, thank you! The first function worked for me!

Neat! Thanks very much, ImkeF

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