[BEAM-11585] Select.flattenedSchema doesn't flatten nested array fields

[Amar3tto]

Fixed Select.flattenedSchema() for nested array fields.

Test case:

Row[] transactions {
  String bank,
  Double purchaseAmount
}
->
String[] transactions_bank,
Double[] transactions_purchaseAmount

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Post-Commit Tests Status (on master branch)

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Java
Python		---			---		---
XLang		---			---		---

Pre-Commit Tests Status (on master branch)

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Non-portable
Portable	---		---	---	---	---

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[Amar3tto]

retest this please

[KhaninArtur]

Everything is looking great! Just one suggestion to add an extended test description

[KhaninArtur]

Let's add a description for this test, I suppose, this way we can provide a much better understanding to interested people. E.g. describe nested schema and expected flattened version of this schema.

[Amar3tto]

Done

[Amar3tto]

retest this please

[pabloem]

Run Java PreCommit

[pabloem]

thanks @Amar3tto @KhaninArtur - is this ready for review/merge?

@TheNeuralBit could you review once it's ready? : )

[TheNeuralBit]

Sure, @Amar3tto please let me know when you're ready for a review.

[Amar3tto]

@TheNeuralBit please review

[TheNeuralBit]

Thanks this looks good at first glance. Could you add some test-cases for edge cases, e.g. I'm curious if we handle:

Row[] transactions {
  String[] banks,
  Double purchaseAmount
}
->
String[][] transactions_banks,
Double[] transactions_purchaseAmount

and:

Row[] transactions {
  Row[] banks {
    String name
    String address
  },
  Double purchaseAmount
}
->
String[][] transactions_banks_name,
String[][] transactions_banks_address,
Double[] transactions_purchaseAmount

[Amar3tto]

Thanks this looks good at first glance. Could you add some test-cases for edge cases, e.g. I'm curious if we handle:

Row[] transactions {
  String[] banks,
  Double purchaseAmount
}
->
String[][] transactions_banks,
Double[] transactions_purchaseAmount

and:

Row[] transactions {
  Row[] banks {
    String name
    String address
  },
  Double purchaseAmount
}
->
String[][] transactions_banks_name,
String[][] transactions_banks_address,
Double[] transactions_purchaseAmount

Done, handled both cases.

[TheNeuralBit]

LGTM, thank you!

[TheNeuralBit]

@Amar3tto consider adding this to CHANGES.md for 2.30.0 as well