Support empty Array of Struct / Do not support null-valued Array of Struct

[MITSUBOSHI]

Issues

• Doesn't support creating an empty array of structs #165

Overview

As mentioned in the issue above, emulator behaves an opposite to the real world Spanner.

Before

SQL	emulator	Spanner(production)
SELECT IF(false, ARRAY<STRUCT<INT64>>[], null)	✅	❌
SELECT IF(false, ARRAY<STRUCT<INT64>>[], [])	❌	✅

After

SQL	emulator	Spanner(production)
SELECT IF(false, ARRAY<STRUCT<INT64>>[], null)	❌	❌
SELECT IF(false, ARRAY<STRUCT<INT64>>[], [])	✅	✅

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[MITSUBOSHI]

@olavloite @skuruppu
Hi, thank you for maintaining the emulator. Could you check and merge this PR :)?

[olavloite]

@olavloite @skuruppu Hi, thank you for maintaining the emulator. Could you check and merge this PR :)?

Hi @MITSUBOSHI

Thanks for reaching out and reporting this issue. We can however not accept pull requests for this repository, because the code is not maintained on GitHub, but rather just exported here from a different (internal) repository.

[MITSUBOSHI]

@olavloite
OK. Then, I submitted this issue to https://issuetracker.google.com/issues/382399965 .
I really hope this issue will be handled and resolved soon!!