获取字段中出现字符串次数最多的记录

Question

Videos Table

Title          date_published
food bag       2011-01-01
bear food bag  2010-02-02
bag mouse      2000-03-03
monitor mouse  2002-03-03

My question is what SQL statement could extract a list of records with the most number of occurrences of food in the title field.

Answer 1

You can count the number of times a string occurs with a replace trick:

select  len(replace(title,'food','food+')) - len(title) as FoodCount
from    Videos

This adds an extra character for each occurrence, and then counts how many extra characters were added.

This SQL Server query selects the top 10 videos with most food:

select  top 10 *
from    (
        select  *
        ,       len(replace(title,'food','food+')) - len(title) as FoodCount
        from    Videos
        ) as SubQueryAlias
order by
        FoodCount desc

For MySQL, you'd remove the top 10 and add limit 10 at the end.