How to Handle Multiple Result Sets in Database Queries?

What are the best practices to manage multiple result sets returned by database queries?

-- SQL example of a query returning multiple result sets
SELECT * FROM customers;
SELECT * FROM orders WHERE customer_id = 1;

Handling multiple result sets in database queries is crucial for efficient data manipulation and retrieval in applications. Various database systems allow multiple result sets to be returned from a single execution context, enhancing flexibility in data operations.

// Example using ADO.NET to handle multiple result sets
using(SqlCommand command = new SqlCommand(query, connection)) {
    SqlDataReader reader = command.ExecuteReader();
    while(reader.Read()) {
        // Process first result set
    }
    if(reader.NextResult()) {
        while(reader.Read()) {
            // Process second result set
        }
    }
}

Causes

• Complex database schemas requiring multiple tables to be queried simultaneously.
• Use of stored procedures that generate multiple result sets for different tasks.

Solutions

• Utilize database drivers or ORM (Object-Relational Mapping) tools that support multiple result sets.
• Implement mechanisms to iterate through each result set systematically within your application code.

Mistake: Not properly managing database connections, leading to resource exhaustion.

Solution: Always ensure that connections are closed after the operation to free up resources.

Mistake: Assuming all drivers support multiple result sets without checking documentation.

Solution: Review the database driver's documentation to confirm support for multiple result sets.