"Invalid cast from 'System.String' to 'System.TimeSpan'." is thrown when getting value of output parameter which its type is TIME

[nhathongly]

I got this exception when trying get the output value of TIME

System.InvalidCastException : Invalid cast from 'System.String' to 'System.TimeSpan'.
 StackTrace:
   at System.Convert.DefaultToType(IConvertible value, Type targetType, IFormatProvider provider)
   at System.String.System.IConvertible.ToType(Type type, IFormatProvider provider)
   at System.Convert.ChangeType(Object value, Type conversionType, IFormatProvider provider)
   at System.Convert.ChangeType(Object value, Type conversionType)
   at MySqlConnector.Core.DbTypeMapping.DoConversion(Object obj) in C:\projects\mysqlconnector\src\MySqlConnector\Core\DbTypeMapping.cs:line 22
   at MySqlConnector.Core.StoredProcedureCommandExecutor.SetParams() in C:\projects\mysqlconnector\src\MySqlConnector\Core\StoredProcedureCommandExecutor.cs:line 108
   at MySql.Data.MySqlClient.MySqlCommand.ReaderClosed() in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlCommand.cs:line 452
   at MySql.Data.MySqlClient.MySqlDataReader.DoClose() in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlDataReader.cs:line 445
   at MySql.Data.MySqlClient.MySqlDataReader.Dispose(Boolean disposing) in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlDataReader.cs:line 282

[bgrainger]

It looks like you might be using a stored procedure with an OUT parameter. Can you provide more details on how to reproduce this, e.g., table definition, stored procedure definition, sample code?

[nhathongly]

My stored procedure is simply like this

CREATE DEFINER=`root`@`%` PROCEDURE `GetTime`(OUT OutTime TIME)
BEGIN
	SET OutTime = CURTIME();
END

I'm totally new to MySql, so I don't know if I get any mistake. It worked perfectly with MySql.Data-8.0.16

[nhathongly]

Hi there,

I experienced the same issue when the data type of OUTPUT parameter is BOOL. The exception said that "Object of type 'System.SByte' cannot be converted to type 'System.Boolean'." when I tried to map the OUTPUT to a bool variable.
Could you have a check?

Thanks

[nhathongly]

When I executed the following script, I saw that the DTD_IDENTIFIER value in information_schema.parameters of a BOOL parameter was TINYINT(1)

SELECT ORDINAL_POSITION, PARAMETER_MODE, PARAMETER_NAME, DTD_IDENTIFIER
FROM information_schema.parameters
WHERE SPECIFIC_SCHEMA = 'DB Name' AND SPECIFIC_NAME = 'Routine Name'
ORDER BY ORDINAL_POSITION;

ORDINAL_POSITION	PARAMETER_MODE	PARAMETER_NAME	DTD_IDENTIFIER
1	IN	js	json
2	OUT	b	tinyint(1)

[nhathongly]

Seem it will be fixed when 782a765 is released

@bgrainger may I know when will we have the next release? Thank you in advance

[bgrainger]

I'll release 0.57.0-beta9 with this fix soon. The beta versions are tested and reliable enough to run in production; they just haven't shipped as a "stable" release yet due to breaking API changes in this series.

[bgrainger]

0.57.0-beta9 is available with this fix.