Query Cache is deterministic

I was reading some points on a Blog post today here . I didn’t see it via Planet MySQL but via a Google Alert.

The post has several good beginner points on MySQL Performance, but included the point “Literal current date is better than using the CURRENT_DATE() function because literals will use the query cache but functions won’t.”

How true, I must admit I’d not considered this in reviewing code for sites that use the Query Cache heavily. Non deterministic functions invalid use of the Query Cache (Except for recent Bug #29053 which is also an interesting read. Note to self, read the new bugs more often when free time permits). Back on point.

So if you have a query like “Select the news for today” and use CURDATE(), it will not be stored in the Query Cache, yet if your application code determines the current date and passes “Select the news for 2007-06-26″ for example it will.

Sometimes the simple things are easy to forget, or not have thought about in this case for me.

Tagged with: Databases MySQL

Related Posts

DataEngBytes Sydney Overview

DataEngBytes Sydney Overview

I have just returned from my first DataEngBytes conference in Sydney. Here is a quick summary on my thoughts for the event. I plan to go into more detail on great points from presentations in later posts.

Read more
MITRE ATLAS - A 2025 Review

MITRE ATLAS - A 2025 Review

The MITRE ATLAS Matrix provides a working knowledge base of adversary tactics, techniques, and real-world case studies specifically for Artificial Intelligence (AI) and Machine Learning (ML) systems. It adapts the established MITRE ATT&CK adversary tactics and techniques matrix which is the standard reference for traditional IT cybersecurity.

Read more
Foundational Frameworks for GenAI Security Analysis

Foundational Frameworks for GenAI Security Analysis

Three frameworks form the analytical foundation of this series’ threat analysis, selected for their complementary coverage of the GenAI security landscape and their broad adoption across enterprise security practices. The MITRE Adversarial Threat Landscape for AI Systems (MITRE ATLAS) maps tactics and techniques specific to AI systems.

Read more