Left Join with multiple tables: not always expected result

问题描述 投票：0回答：1

下面的查询是用于搜索特定玩家的旧游戏和两个玩家的评分变化。 Ratingchanges 存储在自己的名为“ratingverloop”的表中，因为它们需要被保存以用于 ratingchanges 的趋势，而太旧的游戏将在一定时间后被删除。很多时候，ratingchanges 的数据是不正确的。

在屏幕上显示结果集，表明并不总是使用 whitePlayer 和 blackPlayer 的玩家 ID。有时同样被使用两次。

检查MySQL本身的数据，发现了我的问题：对于相同的游戏ID，ratingchanges至少存储了两次。对于这两个球员，他们自己的行。 （用于显示评级随时间变化的图形）。有时在更正/重置游戏的情况下更多。 我已经两次加入 table ratingverloop，每次都是一个玩家。 (rv1,rv2).

但是我怎样才能确定得到正确的行呢？我只是找不到任何关于如何使用左连接的类似示例。 （无论如何我应该在这里使用它，还是有其他解决方案？）

$sql = "SELECT games.gameID
                ,whitePlayer
                ,blackPlayer
                ,gameMessage
                ,messageFrom
                ,date_format(dateCreated , '%d-%m-%Y') AS startdatum
                ,lastMove
                ,date_format(lastMove , '%d-%m-%Y') AS lastMovex
                ,whiteNick
                ,blackNick
                ,rv1.userID AS userID1
                ,rv1.ratingvan AS userID1_ratingvan
                ,rv1.rating AS userID1_rating
                
                ,rv2.userID AS userID2
                ,rv2.ratingvan AS userID2_ratingvan
                ,rv2.rating AS userID2_rating
            
        FROM games 
        LEFT JOIN ratingverloop rv1 ON games.gameID = rv1.gameID
        LEFT JOIN ratingverloop rv2 ON games.gameID = rv2.gameID
        WHERE
            (
                gameMessage <> '' 
                AND gameMessage <> 'playerInvited'
                AND gameMessage <> 'inviteDeclined'
            )
            AND 
            (
                whitePlayer = :playerID
                OR blackPlayer = :playerID
            ) 
            ORDER BY lastMove DESC";

[编辑]如所问：

CREATE TABLE `ratingverloop` (
  `index` int(11) NOT NULL,
  `userID` int(10) UNSIGNED NOT NULL,
  `datumtijd` datetime NOT NULL,
  `gameID` int(11) NOT NULL,
  `ratingvan` smallint(5) UNSIGNED NOT NULL,
  `rating` smallint(5) UNSIGNED NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

--
-- Gegevens worden geëxporteerd voor tabel `ratingverloop`
--

INSERT INTO `ratingverloop` (`index`, `userID`, `datumtijd`, `gameID`, `ratingvan`, `rating`) VALUES
(3071747, 7144, '2023-03-03 00:46:40', 2786547, 1193, 1198),
(3071748, 2187, '2023-03-03 00:46:40', 2786547, 938, 933);

--
-- Indexen voor geëxporteerde tabellen
--

--
-- Indexen voor tabel `ratingverloop`
--
ALTER TABLE `ratingverloop`
  ADD PRIMARY KEY (`index`),
  ADD KEY `userID` (`userID`),
  ADD KEY `gameID` (`gameID`);

结果：

    (
        [gameID] => 2786547
        [whitePlayer] => 2187
        [blackPlayer] => 7144
        [gameMessage] => checkMate
        [messageFrom] => black
        [startdatum] => 23-01-2023
        [lastMove] => 2023-03-03 00:46:40
        [lastMovex] => 03-03-2023
        [whiteNick] => @Gijs
        [blackNick] => E-Street
        [userID1] => 7144
        [userID1_ratingvan] => 1193
        [userID1_rating] => 1198
        [userID2] => 7144
        [userID2_ratingvan] => 1193
        [userID2_rating] => 1198
    )

结果userID1和userID2来自同一行。 应该是：2187和7144

--
-- Tabelstructuur voor tabel `games`
--

CREATE TABLE `games` (
  `gameID` int(20) UNSIGNED NOT NULL,
  `whitePlayer` mediumint(9) DEFAULT NULL,
  `blackPlayer` mediumint(9) DEFAULT NULL,
  `gameMessage` enum('','playerInvited','inviteDeclined','draw','playerResigned','checkMate','VERLOPEN','ONGELDIG','tijdoverschrijding','ingetrokken','stalemate','zettijdoverschrijding') NOT NULL,
  `messageFrom` enum('','black','white','Admin') NOT NULL,
  `wit_rem_aanvraag` datetime NOT NULL,
  `zwart_rem_aanvraag` datetime NOT NULL,
  `rem_antw_zwart` datetime NOT NULL,
  `rem_antw_wit` datetime NOT NULL,
  `dateCreated` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
  `lastMove` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
  `ratingset` enum('notset','set') NOT NULL DEFAULT 'notset',
  `rating_white_start` int(11) DEFAULT NULL,
  `rating_white_end` int(11) NOT NULL DEFAULT '0',
  `rating_black_start` int(11) DEFAULT NULL,
  `rating_black_end` int(11) NOT NULL DEFAULT '0',
  `notitie_wit` text NOT NULL,
  `notitie_zwart` text NOT NULL,
  `vak_wit` date NOT NULL DEFAULT '0000-00-00',
  `vak_zwart` date NOT NULL DEFAULT '0000-00-00',
  `her_invite` tinyint(4) NOT NULL DEFAULT '0',
  `pionpromo` tinyint(4) NOT NULL DEFAULT '0',
  `beurtaan` tinytext NOT NULL,
  `whiteNick` tinytext,
  `blackNick` tinytext,
  `kibW` enum('ja','nee') NOT NULL DEFAULT 'ja',
  `kibZ` enum('ja','nee') NOT NULL DEFAULT 'ja',
  `comment` tinytext NOT NULL,
  `witOnline` datetime NOT NULL,
  `zwartOnline` datetime NOT NULL,
  `chataanvraagdoor` int(10) UNSIGNED NOT NULL,
  `chataanvraagtijd` datetime NOT NULL DEFAULT '1900-00-00 00:00:00',
  `ftoernooi` enum('0','1') NOT NULL DEFAULT '0',
  `tafel` enum('0','1') NOT NULL DEFAULT '0',
  `ratingrange` smallint(5) UNSIGNED NOT NULL DEFAULT '500',
  `speeltijd` mediumint(3) UNSIGNED DEFAULT NULL,
  `speeltijdwit` mediumint(8) UNSIGNED NOT NULL,
  `speeltijdzwart` mediumint(8) UNSIGNED NOT NULL,
  `maxzettijd` time NOT NULL DEFAULT '168:00:00',
  `startklok` datetime NOT NULL,
  `opener` mediumint(8) UNSIGNED DEFAULT NULL,
  `ts_ladder` tinyint(3) UNSIGNED DEFAULT NULL COMMENT 'teamschaken laddertoernooi',
  `t_partij` tinyint(3) UNSIGNED NOT NULL DEFAULT '0',
  `tt` tinyint(3) UNSIGNED NOT NULL COMMENT 'teamtoernooi',
  `rated` tinyint(3) UNSIGNED NOT NULL DEFAULT '1',
  `klok` tinyint(4) NOT NULL DEFAULT '0',
  `toernooisoort` tinyint(10) UNSIGNED NOT NULL DEFAULT '0' COMMENT '0 = geen toernooi, 1 = tsreg',
  `vakmodus` tinyint(4) NOT NULL DEFAULT '0',
  `50zetten` tinyint(3) UNSIGNED NOT NULL DEFAULT '0'
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COMMENT='herinvite: 1=uitnodiging, 2 voor lopende partij';

--
-- Gegevens worden geëxporteerd voor tabel `games`
--

INSERT INTO `games` (`gameID`, `whitePlayer`, `blackPlayer`, `gameMessage`, `messageFrom`, `wit_rem_aanvraag`, `zwart_rem_aanvraag`, `rem_antw_zwart`, `rem_antw_wit`, `dateCreated`, `lastMove`, `ratingset`, `rating_white_start`, `rating_white_end`, `rating_black_start`, `rating_black_end`, `notitie_wit`, `notitie_zwart`, `vak_wit`, `vak_zwart`, `her_invite`, `pionpromo`, `beurtaan`, `whiteNick`, `blackNick`, `kibW`, `kibZ`, `comment`, `witOnline`, `zwartOnline`, `chataanvraagdoor`, `chataanvraagtijd`, `ftoernooi`, `tafel`, `ratingrange`, `speeltijd`, `speeltijdwit`, `speeltijdzwart`, `maxzettijd`, `startklok`, `opener`, `ts_ladder`, `t_partij`, `tt`, `rated`, `klok`, `toernooisoort`, `vakmodus`, `50zetten`) VALUES
(2786547, 2187, 7144, 'checkMate', 'black', '0000-00-00 00:00:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', '0000-00-00 00:00:00', '2023-01-23 22:11:26', '2023-03-03 00:46:40', 'set', NULL, 0, NULL, 0, '', '', '0000-00-00', '0000-00-00', 0, 0, '2187', '@Gijs', 'E-Street', 'ja', 'ja', '', '2023-03-02 21:58:22', '2023-03-03 00:46:56', 0, '1900-00-00 00:00:00', '0', '0', 500, NULL, 0, 0, '168:00:00', '2023-01-24 09:06:01', NULL, NULL, 0, 0, 1, 0, 0, 0, 6);

--
-- Indexen voor geëxporteerde tabellen
--

--
-- Indexen voor tabel `games`
--
ALTER TABLE `games`
  ADD UNIQUE KEY `gameID_2` (`gameID`),
  ADD KEY `gameID` (`gameID`),
  ADD KEY `idx_partijlijst_datum` (`gameMessage`,`lastMove`),
  ADD KEY `inx_tafel` (`tafel`),
  ADD KEY `idx2_whitePlayer` (`whitePlayer`),
  ADD KEY `idx2_blackPlayer` (`blackPlayer`),
  ADD KEY `toernooisoort` (`toernooisoort`),
  ADD KEY `vakmodus` (`vakmodus`),
  ADD KEY `expired_games` (`lastMove`,`ratingset`,`vak_wit`,`vak_zwart`,`ts_ladder`,`klok`);

--
-- AUTO_INCREMENT voor geëxporteerde tabellen
--

--
-- AUTO_INCREMENT voor een tabel `games`
--
ALTER TABLE `games`
  MODIFY `gameID` int(20) UNSIGNED NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=2795936;
mysql sql join left-join
1个回答
1
投票

您需要在加入条件中包含白色和黑色用户ID：

LEFT JOIN ratingverloop rv1 
    ON games.gameID = rv1.gameID AND games.whitePlayer = rv1.userID
LEFT JOIN ratingverloop rv2 
    ON games.gameID = rv2.gameID AND games.blackPlayer = rv2.userID
最新问题
© www.soinside.com 2019 - 2024. All rights reserved.