Unable to handle SQL_VARIANT types

[david-garcia-garcia]

The PDO driver is chocking on SQL_VARIANT types, but this can contain themselves simple types such as char, intenger, etc...

Steps to reproduce:

1. Create an UDF:

CREATE FUNCTION [dbo].[GREATEST](@OP1 sql_variant, @OP2 sql_variant) RETURNS sql_variant AS
BEGIN
DECLARE @Result sql_variant
SET @Result = CASE WHEN @OP1 >= @OP2 THEN @OP1 ELSE @OP2 END
RETURN @Result
END
GO

1. Run this query through the PDO

SELECT dbo.GREATEST(5, 6)

1. Theses are the errors you get:

Without Buffered Queries:

SQLSTATE[IMSSP]: Invalid type.

With Buffered Queries:

Fatal error: Unknown type in sqlsrv_buffered_query::sqlsrv_buffered_query

I can manage to get it to work if I use PDO::PARAM_INT on the column before the fetch, but there is no way that I can infer this informatino from the PDO metadata (getColumnMeta) that is reporting:

sql_srv_type = sql_variant
native_type = string

Possible solutions.....

1. At least let me retrieve the data as a string by default, instead of Fatal crashing.

[stevebauman]

This is still an issue today running IIS 10 / PHP 7.1.1 / using SQLSRV RC 4.1.3. Is there a fix in the works?

[Hadis-Fard]

@stevebauman PHP drivers rely on ODBC to handle SQL data types, and SQL_VARIANT is not supported in ODBC. We're looking into David's suggestion to see if SQL variants can be handled with string inferred type.

[stevebauman]

@Hadis-Fard Awesome! Thanks for the reply :).

[Hadis-Fard]

@stevebauman @david-garcia-garcia we added support for sql variants in 4.2.0-preview, you can get the driver from our PECL repositiry or GitHub releases page. Note that sqlvariant for output parameters is not supported.