The question of whether one big query is faster than many small queries in MySQL (or any database management system) is complex and depends on various factors, including the specific use case, the database schema, the amount of data involved, and the database server's configuration. Both approaches have their advantages and disadvantages, and the optimal choice often depends on the context of the application and the nature of the data being queried.
Advantages of One Big Query:
Reduced Network Latency: A single query reduces the overhead of multiple round-trips between the application and the database server, which can be significant in client-server database systems[16].
Optimized Execution Plan: The database's query optimizer can generate a more efficient execution plan when all the data requirements are specified in one query, as it has a complete view of the data needs[2][7].
Transactional Integrity: A single query ensures that all the data is retrieved in a consistent state, which is particularly important for complex operations that need to be atomic[7].
Advantages of Many Small Queries:
Simplicity and Maintainability: Smaller queries can be easier to understand, maintain, and debug, especially when different parts of the data are handled by different components of an application[16][17].
Flexibility: Small queries allow for more dynamic and flexible data retrieval strategies, where the application can decide on-the-fly which data is needed based on user input or other conditions[16].
Efficiency for Specific Use Cases: In some scenarios, especially when dealing with SQLite or when the application and database are running in the same process space, many small queries do not suffer from the same network latency issues and can be very efficient[16].
Considerations:
Database Engine: Different database engines have different optimizations. For example, SQLite is designed to efficiently handle many small queries due to its architecture, which is different from client/server systems like MySQL[16].
Data Size and Complexity: The size of the data and the complexity of the operations being performed can influence the decision. Complex operations involving multiple joins and aggregations mi...
