siliconpi
Reputation: 8297
Storing empty strings vs NULLs in MySQL database?
I have a PHP/MySQL application that stores "blank" values in some cases as '' (empty strings) and in other cases as NULLs.
Having this mixed format certainly causes a problem when comparing, so I’m wondering which one is the better storage mechanism? '' or NULL?
Upvotes: 5
Views: 2850
Answers (1)
Simone Gianni
Reputation: 11672
While this is confusing, actually you should store null for a number of reasons :
- Checking against null is usually faster than checking an empty string in most databases
- Null commonly means "i don't know", empty string means "I know : it's empty". It gives you better semantics.
Upvotes: 8
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