How Can I Efficiently Query MySQL for Exact Matches in Comma-Separated Value Fields?

Optimizing MySQL Queries for Comma-Separated Values

Let's examine a SHIRTS table with a COLORS field storing comma-separated numeric color codes. A simple LIKE query can yield inaccurate results:

SELECT * FROM shirts WHERE colors LIKE '%1%'

This query returns shirts containing '1' anywhere in the colors field, including shirts with colors like 1, 12, or 15. To find only shirts with color code 1, we need more precise methods.

One effective technique involves flanking the colors string with commas before comparison:

SELECT * FROM shirts WHERE CONCAT(',', colors, ',') LIKE '%,1,%'

This ensures that only color code 1, precisely delimited by commas, is matched.

Another efficient approach uses the FIND_IN_SET() function:

SELECT * FROM shirts WHERE FIND_IN_SET('1', colors) > 0

FIND_IN_SET() directly checks for the existence of '1' within the comma-separated list in the colors field, providing accurate results. This method is generally preferred for its clarity and efficiency.

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