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Object cannot be cast from DBNull to other types" (mariadb 10.3)
An Azure managed MariaDB database service for app development and deployment.
An Azure managed MySQL database service for app development and deployment.
An object-oriented and type-safe programming language that has its roots in the C family of languages and includes support for component-oriented programming.
@kriangkrai kongsamlee, Welcome to Microsoft Q&A, could you provide some c# code with me? I will have a test for it.
@kriangkrai kongsamlee are you still facing the issue? can you please provide more information on the error?
Regards
Geetha
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Hi, I have the same problem. When my C# code wants to make a SQL-connection I the error mentioned:
System.InvalidCastException: 'Object cannot be cast from DBNull to other types.'
Source: "mscorlib"
The problem started when I got a new laptop. Unfortunately the old one is wiped already.
I am not sure if this has anything to do with a column (like in the answer).
What can I do?
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That is correct. when a column value is null, the object DBNull is returned rather than a typed value. You must first test that the column value is not null via the api before accessing as the desired type.
If you use the Connector/NET (i.e., MySql.Data), try using the MySqlConnector instead of MySql.Data.
References:
MySQL Connector fails to connect to MariaDB 10.10.2
MySqlConnection.Open() System.InvalidCastException: Object cannot be cast from DBNull to other types