SQL queries Vs Stored procedures

The speed of execution between plain SQL queries and stored procedures often depends on the specific context, but here’s a general comparison: 

Stored Procedures are Typically Faster

1. Precompilation: Stored procedures are precompiled and their execution plans are cached by the database server. This means that the database engine does not need to parse and compile the SQL code each time the procedure is executed, which can lead to faster execution for repeated calls.

2. Optimized Execution: Stored procedures can be optimized by the database engine based on the stored logic. This optimization can include efficient use of indexes and execution plans that are better suited to the stored procedure's logic.

3. Reduced Overhead: When using stored procedures, the database server performs less overhead related to parsing and planning compared to executing a new plain SQL query each time.

 Plain SQL Queries

1. Ad-hoc Execution: Each plain SQL query is parsed, compiled, and executed individually. This can introduce overhead, especially for complex queries or those executed frequently.

2. Caching: While the database engine can cache execution plans for queries, this is generally less efficient compared to the precompilation and caching of stored procedures. 

Factors Influencing Performance

- Query Complexity: For simple queries, the performance difference may be negligible. For complex queries with many joins, filters, or business logic, stored procedures usually provide better performance.

- Database Server: Different database systems may have different optimizations and caching mechanisms, which can affect the relative performance.

- Execution Frequency: Stored procedures are particularly beneficial when the same query or logic is executed frequently, due to their precompiled nature and reduced parsing overhead.

- Parameterization: Both stored procedures and parameterized queries (when using plain SQL) can help reduce SQL injection risks and can improve performance through parameter sniffing.

SQL queries Vs Stored procedures Conclusion

In general, stored procedures are often faster than plain SQL queries due to their precompilation and optimized execution. However, the actual performance gain can vary based on the specific use case, query complexity, and the database system used. For complex operations or frequently executed logic, stored procedures are usually the better choice for performance.