Query: Translate byte array.IndexOf

[smitpatel]

[smitpatel]

CharIndex over varbinary(max) returns bigint rather than int.

[ralmsdeveloper]

[Edited name]
I'm on vacation, and I want to get some things to do, can I start with this one, @roji / @smitpatel any observation?

[roji]

Nothing in particular @ralmsdeveloper, just to pay close attention to specific return types (bigint/int) as @smitpatel wrote above.

[nikhil197]

Hi @roji / @smitpatel

I am new to the EFCore repo and have just understood some basic things about the translation (above linked PR helped with that a bit).
I would like to work on this one if it's not being worked on by any one else.

Here's my initial understanding of this issue (atleast for SqlServer):

• Need to add a specific translator for the ByteArray for the 2 overloads of Array.IndexOf method in SqlServerByteArrayMethodTranslator
• In case the declaring type is varbinary(max) cast the return value as int before returning

Haven't looked into sqlLite for this yet, but it should be easily portable. Before that I wanted to check if I'm on the right track for this?

[roji]

@nikhil197 overall yes, but what are you planning to translate the method call to exactly? And why "cast the return value as int"? Note that you'll also need to add proper test coverage too.

I'd suggest on concentrating on a SQL Server implementation first, it's also OK if support is added only for SQL Server initially without SQLite (although support in both is obviously better).

[nikhil197]

@roji
I have tried implementing similar to what has already been done for the string.IndexOf methods. Passing values to CHARINDEX (with conversions, if needed) and then returning value - 1 (since CHARINDEX returns 1-based values).
This is the final translation for the Array.IndexOf method for byte[], with a starting position:
CAST(CHARINDEX(CAST(@__b_0 AS varbinary(max)), [s].[Banner], @__startPos_1 + 1) AS int) - 1

And casting to int is only when varbinary(max) is the underlying type of the column because as mentioned above, CHARINDEX will return bigint. So to match that to the method which returns int, I'm using a cast.

And I have tried adding tests as well. I was starting to look into the SQLite change, but I can raise the PR for the changes I have done so far.