我有一张这样的桌子:
TITLE | DESCRIPTION
------------------------------------------------
test1 | value blah blah value
test2 | value test
test3 | test test test
test4 | valuevaluevaluevaluevalue
我想弄清楚如何返回字符串在每个描述中出现的次数.
I am trying to figure out how to return the number of times a string occurs in each of the DESCRIPTION's.
所以,如果我想统计'value'出现的次数,sql语句会返回这个:
So, if I want to count the number of times 'value' appears, the sql statement will return this:
TITLE | DESCRIPTION | COUNT
------------------------------------------------------------
test1 | value blah blah value | 2
test2 | value test | 1
test3 | test test test | 0
test4 | valuevaluevaluevaluevalue | 5
有没有办法做到这一点?我根本不想用php,就用mysql.
Is there any way to do this? I do not want to use php at all, just mysql.
这应该可以解决问题:
SELECT
title,
description,
ROUND (
(
LENGTH(description)
- LENGTH( REPLACE ( description, "value", "") )
) / LENGTH("value")
) AS count
FROM <table>
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