Utilizing User Defined Variables in MySql Commands for .NET
User defined variables play a crucial role in MySql queries, enabling the manipulation of temporary data within stored procedures or queries. However, integrating these variables into .NET MySqlCommand objects presents a challenge. This article addresses the error encountered when attempting to use @rownum variables in .NET code.
To execute the provided SQL statement using the MySqlAdapter, it is necessary to modify the connection string to include ";Allow User Variables=True." This addition instructs the .NET Connector to recognize and utilize user defined variables within the query.
The updated connection string should resemble the following:
using (var sqlConnection = new MySqlConnection(SOURCE_CONNECTION + ";Allow User Variables=True")) { ... }
With the modified connection string, the MySqlAdapter will now successfully execute the query, recognizing @rownum as a user defined variable. The resulting DataTable will contain the desired row numbering based on the inner scalar query.
For a more comprehensive discussion on this topic, refer to the blog post mentioned in the answer:
"How can I use a MySql User Defined Variable in a .NET MySqlCommand?"
The above is the detailed content of How can I use MySQL User-Defined Variables in a .NET MySqlCommand?. For more information, please follow other related articles on the PHP Chinese website!

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