section:
article:
the requirement is to query out all the fields of the forum at once, and the first 10 articles belonging to this section (field id,title,content is fine). The sid in article corresponds to the id in section
.
section:
article:
the requirement is to query out all the fields of the forum at once, and the first 10 articles belonging to this section (field id,title,content is fine). The sid in article corresponds to the id in section
.you can do this:
SELECT *, result.row_number
FROM
(SELECT *, (@num:=IF(@group = `sid`, @num +1, IF(@group := `sid`, 1, 1))) row_number
FROM article
ORDER BY sid) result
WHERE row_number <= 10
;article table is sorted by sid, and then one row_number, per row is calculated as shown above.
I hope I can help you.
I follow your operation, the first query will query all the data. The second query got the expected results.
first query result:
:
the number of results of the two queries is inconsistent. The row_number of the first query is 1, and the second query is the correct result. I don't know why this happened. Is there anyone who can answer it?
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