DECLARE @a VARCHAR(200) = 'http://a.com/1.jpg||http://a.com/2.jpg||http://a.com/4.jpg||http://a.com/8.jpg||http://a.com/10.jpg||http://a.com/11.jpg'

SELECT (len(@a)-LEN(REPLACE(@a,'||','')))/2+1

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------解决方案--------------------
SQL code

DECLARE @A VARCHAR(1000)
SET @a = 'http://a.com/1.jpg||http://a.com/2.jpg||http://a.com/4.jpg||http://a.com/8.jpg||http://a.com/10.jpg||http://a.com/11.jpg'

SELECT (LEN(@A) - LEN(REPLACE(@A,'http',''))) / 4

(No column name)
6