Retrieving the Identifier of an Inserted Row using C#
In a database table containing an auto-incremented "ID" field, obtaining the ID of a recently inserted row proves to be a recurring task. This becomes particularly crucial for subsequent operations dependent on the ID.
In your case, despite executing an insertion command, the ID value retrieved consistently returned zero. This discrepancy arises from the use of ExecuteScalar, which retrieves the first column of the first row returned by the command. Since no specific column is projected, the value at the first index is retrieved. However, auto-incremented IDs are generally generated after the command insertion, resulting in the ID column initially containing nothing.
To address this issue, consider modifying your code as follows:
MySqlCommand comm = connect.CreateCommand(); comm.CommandText = insertStatement; // Set the insert statement comm.ExecuteNonQuery(); // Execute the command long id = comm.LastInsertedId; // Get the ID of the inserted item
The critical difference lies in the use of ExecuteNonQuery, which specifically executes the insert statement without returning a value. Subsequently, calling LastInsertedId retrieves the generated ID value directly.
This approach aligns with the requirement to retrieve the auto-incremented ID, eliminating the issue encountered with ExecuteScalar.
The above is the detailed content of How to Retrieve the ID of an Inserted Row using C#?. For more information, please follow other related articles on the PHP Chinese website!