问题
So a field called schools in the database might have a value of:
'13,121,112,1212'
I'm using that to show the potential for a mistake.
Suppose I'm looking for a value of 12 in that field. The commas denote a "whole number" and I don't want to match 112 or 1212
Is there a more elegant match than this?
@compare = 12;
WHERE CONCAT(schools,',') LIKE CONCAT('%',compare,',%)
I was recently impressed by the GROUP_CONCAT function but this is kind of in reverse of that. Thanks!
回答1:
For this simple case you can use FIND_IN_SET();
WHERE FIND_IN_SET('13', schools);
Note though that there is no good indexing for columns with comma separated text, so the queries will be much slower than a normalized database.
来源：https://stackoverflow.com/questions/35902898/mysql-compare-comma-separated-field-with-single-string