我有一個來自我以前的問題(link)關於複雜的選擇, 查詢,我的問題是,我怎麼能寫這個查詢的結果更新查詢,將fet_id更改爲一些新的值。如何爲此SELECT查詢編寫UPDATE查詢?
請注意,此查詢將從隊列中選擇行,直到rcpts_count達到1000(用於流量控制)。有關此查詢的更多信息是,in this question
SELECT NULL AS msg_id, NULL AS total, NULL AS found
FROM dual
WHERE (
@total :=0
OR
@found :=0
)
UNION
SELECT msg_id, @total AS total, @found :=1 AS found
FROM messages_queue
WHERE (
@total := @total + rcpts_count
)
AND @total <1000
UNION
SELECT msg_id, rcpts_count AS total, 0 AS found
FROM messages_queue
WHERE IF(@found =0, @found :=1, 0)
想要更新上表中返回的集合中的所有記錄,將字段'fet_id'設置爲整個集合的單個值嗎? –