將多行插入單行mysql

Question

以下腳本旨在具有以下功能：

1. 在eurusd_m1中找到一行，其中volume = 250，
2. 在第1行之前找到行
3. 在第一行之后找到第一行

4. 將每行中的所需值復制到obsh4中的單行中

    Create procedure doji_result () begin DECLARE initial DATETIME; DECLARE final DATETIME; DECLARE centre DATETIME; DECLARE x int; SET x = 0; SET @initial = (select MQLTime from eurusd_m1 where volume=250 order by mqltime asc limit 1); SET @final = (select MQLTime from eurusd_m1 where volume=250 order by mqltime desc limit 1); REPEAT SET @centre = (select MQLTime from eurusd_m1 where volume=250 order by mqltime asc limit x,1); INSERT INTO obsh4 (MQLrefTime,RrefTime,Open,High,Low,Close,Volume) select MQLTime,RTime,Open,high,Low,Close,Volume from eurusd_m1 where MQLTime = @centre order by MQLTime asc limit 1; INSERT INTO obsh4 (Open2,High2,Low2,Close2,Volume2) select Open,high,Low,Close,Volume from eurusd_m1 where MQLTime < @centre order by MQLTime desc limit 1; INSERT INTO obsh4 (Open3,High3,Low3,Close3,Volume3) select Open,high,Low,Close,Volume from eurusd_m1 where MQLTime > @centre order by MQLTime asc limit 1; SET x=x+1; UNTIL @centre=@final END REPEAT; END $$ DELIMITER ; 

   當我運行此代碼時，eurusd_m1中的每一行都將被復制到obsh4中的新行中（而不是在每次循環迭代時將所有三行都折疊成一行）

   我嘗試使用UPDATE通過以下腳本添加第二行和第三行數據，但是我在FROM上遇到了語法問題，而且我不確定如何解決這個問題：/

    update obsh4 set Open2 = open, High2 = high, Low2 = low, Close2 = close, Volume2 = volume, from select Open,high,Low,Close,Volume from eurusd_m1 where MQLTime < @centre order by MQLTime desc limit 1; 

我可以看到三個選項：

1）更新語句需要糾正

2）第二行/第三行的插入需要添加行規范

3）分箱並從頭開始生成某些東西。

關於這兩個方面的任何建議都將受到歡迎。 謝謝

編輯：循環本身正常運行，並且已獨立於當前問題進行了測試。

Answer 1

這段冗長的代碼解決了問題。 我想我可以簡化一些，所以我很願意提出建議。

drop procedure if exists doji_result; 
DELIMITER $$
Create procedure doji_result ()
begin 

DECLARE final DATETIME;
DECLARE centre DATETIME;
DECLARE openB1 DOUBLE;
DECLARE highB1 DOUBLE;
DECLARE lowB1 DOUBLE;
DECLARE closeB1 DOUBLE;
DECLARE volumeB1 DOUBLE;
DECLARE openA1 DOUBLE;
DECLARE highA1 DOUBLE;
DECLARE lowA1 DOUBLE;
DECLARE closeA1 DOUBLE;
DECLARE volumeA1 DOUBLE;

DECLARE x int;

SET x = 0;

SET @final = (select MQLTime from eurusd_m1 where volume=250 
order by mqltime desc limit 1);

REPEAT

SET @centre = (select MQLTime from eurusd_m1 where volume=250 
order by mqltime asc limit x,1);

SET @openB1 = (select open from eurusd_m1 where MQLtime < @centre order by mqltime desc limit 1);
SET @highB1 = (select high from eurusd_m1 where MQLtime < @centre order by mqltime desc limit 1);
SET @lowB1 = (select low from eurusd_m1 where MQLtime < @centre order by mqltime desc limit 1);
SET @closeB1 = (select close from eurusd_m1 where MQLtime < @centre order by mqltime desc limit 1);
SET @volumeB1 = (select volume from eurusd_m1 where MQLtime < @centre order by mqltime desc limit 1);

SET @openA1 = (select open from eurusd_m1 where MQLtime > @centre order by mqltime asc limit 1);
SET @highA1 = (select high from eurusd_m1 where MQLtime > @centre order by mqltime asc limit 1);
SET @lowA1 = (select low from eurusd_m1 where MQLtime > @centre order by mqltime asc limit 1);
SET @closeA1 = (select close from eurusd_m1 where MQLtime > @centre order by mqltime asc limit 1);
SET @volumeA1 = (select volume from eurusd_m1 where MQLtime > @centre order by mqltime asc limit 1);

INSERT INTO obsh4 (MQLrefTime,RrefTime,Open,High,Low,Close,Volume) 
select MQLTime,RTime,Open,high,Low,Close,Volume 
from eurusd_m1 where MQLTime = @centre 
order by MQLTime asc limit 1; 

update obsh4
SET open2 = @openB1,
    high2 = @highB1,
    low2 = @lowB1,
    close2 = @closeB1,
    volume2 = @volumeB1,
    open3 = @openA1,
    high3 = @highA1,
    low3 = @lowA1,
    close3 = @closeA1,
    volume3 = @volumeA1
order by mqlreftime desc limit 1;

SET x=x+1;

UNTIL @centre=@final
END REPEAT;

END $$
DELIMITER ;