问题
I have this query:
SELECT * FROM mytable
WHERE column1 LIKE '%word1%'
AND column1 LIKE '%word2%'
AND column1 LIKE '%word3%'
I need to modify this query to return records for which column1 contains word1 word2 and word3 and nothing else! no other words, just these words.
Example: searching for samsung galaxy s3 should return any combination of samsung s3 galaxy but NOT samsung galaxy s3 lte
回答1:
Assuming that column1 contains space separated words, and you only want to match on whole words, something like:
SELECT * FROM
(select ' ' + REPLACE(column1,' ',' ') + ' ' as column1 from mytable) t
WHERE
column1 like '% word1 %' AND
column1 like '% word2 %' AND
column1 like '% word3 %' AND
REPLACE(REPLACE(REPLACE(column1,
' word1 ',''),
' word2 ',''),
' word3 ','') = ''
Note that this construction does allow the same word to appear multiple times. It's not clear from the question whether that should be allowed. (Fiddle)
It would be a far better design if these words were stored as separate rows in a separate table that relates back to mytable. We could then use more normal SQL to satisfy this query. Your example looks like it's some kind of tagging example. Having a table storing each tag as a separate row (with an ordinal position also recorded, if required) would turn this into a simple relational division problem.
A way to count how many times a word appears in a column is the expression:
(LEN(column2) - LEN(REPLACE(column2,'word',''))/LEN('word')
but this would again revert back to matching subsequences of larger words as well as the word itself, without more work.
回答2:
Try This
SELECT * FROM mytable
WHERE column1 LIKE 'word1'
AND column1 LIKE 'word2'
AND column1 LIKE 'word3'
回答3:
in MySQL you can use regexp as
SELECT * FROM mytable
WHERE column1 regexp '^word[1-3]$';
in postgres you can use 'similar to' key word
i think oracle also has regexp
来源:https://stackoverflow.com/questions/14291060/sql-select-like-containing-only-specific-words