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社区首页 >问答首页 >更新查询不能工作7-8%的记录

问更新查询不能工作7-8%的记录
EN

Stack Overflow用户
提问于 2019-08-30 12:44:50
回答 2查看 60关注 0票数 1

我想这并不容易。我有一个简单的更新查询，运行良好，问题是7-8%的记录没有更新。左联接似乎并不总是与ON子句匹配。

我已经检查了不匹配的字段，看看是否有一些空白，但没有。我还检查了左边表中的副本，这里也没有。当然，我还检查了两个表中的记录是否都存在。

我在Windows10下使用MySQL 8.0

这是我的密码：

代码语言：javascript
复制
  UPDATE `61_LoadUnit`
    LEFT JOIN `statistics`.`tbl_g08t1`
    ON `61_LoadUnit`.`StUnit` = `statistics`.`tbl_g08t1`.`ecarrno`
    SET `61_LoadUnit`.`carrno` = `statistics`.`tbl_g08t1`.`carrno`
    WHERE `61_LoadUnit`.`carrno` IN (NULL, 0);

StUnit=29318284的一些数据。对不起，我不知道如何粘贴桌子。

​

代码语言：javascript
复制
61_loadunit
<html>
  <head>
    <title>61_loadunit</title>
    <meta name="GENERATOR" content="HeidiSQL 10.2.0.5599">
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <style type="text/css">
      thead tr {background-color: ActiveCaption; color: CaptionText;}
      th, td {vertical-align: top; font-family: "Tahoma", Arial, Helvetica, sans-serif; font-size: 8pt; padding: 3px; }
      table, td {border: 1px solid silver;}
      table {border-collapse: collapse;}
      thead .col0 {width: 64px;}
      thead .col1 {width: 89px;}
      thead .col2 {width: 83px;}
      thead .col3 {width: 90px;}
      thead .col4 {width: 52px;}
      thead .col5 {width: 51px;}
      thead .col6 {width: 35px;}
      thead .col7 {width: 35px;}
      thead .col8 {width: 89px;}
      thead .col9 {width: 95px;}
      thead .col10 {width: 83px;}
      .col10 {text-align: right;}
      thead .col11 {width: 88px;}
      .col11 {text-align: right;}
      thead .col12 {width: 157px;}
      thead .col13 {width: 67px;}
      thead .col14 {width: 71px;}
      thead .col15 {width: 70px;}
      .col15 {text-align: right;}
      thead .col16 {width: 87px;}
      .col16 {text-align: right;}
      thead .col17 {width: 147px;}
      thead .col18 {width: 83px;}
    </style>
  </head>
  <body>
    <table caption="61_loadunit (3 rows)">
      <thead>
        <tr>
          <th class="col0">Division</th>
          <th class="col1">Confirmation</th>
          <th class="col2">RefID</th>
          <th class="col3">WCS_LoadId</th>
          <th class="col4">MHA</th>
          <th class="col5">Rack</th>
          <th class="col6">X</th>
          <th class="col7">Y</th>
          <th class="col8">StUnit</th>
          <th class="col9">Weight_LW61</th>
          <th class="col10">carrno</th>
          <th class="col11">Shortl62</th>
          <th class="col12">Partno</th>
          <th class="col13">PartRev</th>
          <th class="col14">DivCode</th>
          <th class="col15">Quantity</th>
          <th class="col16">partwght</th>
          <th class="col17">CreationDateTime</th>
          <th class="col18">RunDate</th>
        </tr>
      </thead>
      <tbody>
        <tr>
          <td class="col0">WCS1</td>
          <td class="col1">0</td>
          <td class="col2">10762181</td>
          <td class="col3">10762181</td>
          <td class="col4">ID1</td>
          <td class="col5"></td>
          <td class="col6"></td>
          <td class="col7"></td>
          <td class="col8">AKS22282</td>
          <td class="col9">482.00</td>
          <td class="col10">32614650</td>
          <td class="col11">166540</td>
          <td class="col12">RB-12.7/G16VX310A       </td>
          <td class="col13">      </td>
          <td class="col14">AKS   </td>
          <td class="col15">54000</td>
          <td class="col16">0.008454</td>
          <td class="col17">2019-08-29T14:52:09Z</td>
          <td class="col18">20190830</td>
        </tr>
        <tr>
          <td class="col0">WCS1</td>
          <td class="col1">0</td>
          <td class="col2">10762178</td>
          <td class="col3">10762178</td>
          <td class="col4">ID1</td>
          <td class="col5"></td>
          <td class="col6"></td>
          <td class="col7"></td>
          <td class="col8">799197533</td>
          <td class="col9">126.20</td>
          <td class="col10">32577072</td>
          <td class="col11">223198</td>
          <td class="col12">PER.UCFX12A-A           </td>
          <td class="col13">33 47 </td>
          <td class="col14">479PBE</td>
          <td class="col15">15</td>
          <td class="col16">5.8</td>
          <td class="col17">2019-08-29T14:51:49Z</td>
          <td class="col18">20190830</td>
        </tr>
        <tr>
          <td class="col0">WCS1</td>
          <td class="col1">0</td>
          <td class="col2">10762172</td>
          <td class="col3">10762172</td>
          <td class="col4">ID1</td>
          <td class="col5"></td>
          <td class="col6"></td>
          <td class="col7"></td>
          <td class="col8">29318284</td>
          <td class="col9">223.80</td>
          <td class="col10"></td>
          <td class="col11"></td>
          <td class="col12"></td>
          <td class="col13"></td>
          <td class="col14"></td>
          <td class="col15"></td>
          <td class="col16"></td>
          <td class="col17">2019-08-29T14:51:29Z</td>
          <td class="col18">20190830</td>
        </tr>
      </tbody>
    </table>
  </body>
</html>

tbl_g08t1
<html>
  <head>
    <title>tbl_g08t1</title>
    <meta name="GENERATOR" content="HeidiSQL 10.2.0.5599">
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <style type="text/css">
      thead tr {background-color: ActiveCaption; color: CaptionText;}
      th, td {vertical-align: top; font-family: "Tahoma", Arial, Helvetica, sans-serif; font-size: 8pt; padding: 3px; }
      table, td {border: 1px solid silver;}
      table {border-collapse: collapse;}
      thead .col0 {width: 87px;}
      .col0 {text-align: right;}
      thead .col1 {width: 91px;}
      .col1 {text-align: right;}
      thead .col2 {width: 77px;}
      .col2 {text-align: right;}
      thead .col3 {width: 69px;}
      .col3 {text-align: right;}
      thead .col4 {width: 66px;}
      .col4 {text-align: right;}
      thead .col5 {width: 74px;}
      .col5 {text-align: right;}
      thead .col6 {width: 50px;}
      .col6 {text-align: right;}
      thead .col7 {width: 71px;}
      .col7 {text-align: right;}
      thead .col8 {width: 62px;}
      .col8 {text-align: right;}
      thead .col9 {width: 46px;}
      .col9 {text-align: right;}
      thead .col10 {width: 62px;}
      .col10 {text-align: right;}
      thead .col11 {width: 64px;}
      thead .col12 {width: 54px;}
      thead .col13 {width: 65px;}
      thead .col14 {width: 65px;}
      thead .col15 {width: 56px;}
      thead .col16 {width: 63px;}
      thead .col17 {width: 70px;}
      .col17 {text-align: right;}
      thead .col18 {width: 63px;}
      .col18 {text-align: right;}
      thead .col19 {width: 62px;}
      .col19 {text-align: right;}
      thead .col20 {width: 69px;}
      .col20 {text-align: right;}
      thead .col21 {width: 87px;}
      .col21 {text-align: right;}
      thead .col22 {width: 69px;}
      .col22 {text-align: right;}
      thead .col23 {width: 93px;}
      .col23 {text-align: right;}
      thead .col24 {width: 138px;}
      thead .col25 {width: 138px;}
      thead .col26 {width: 138px;}
      thead .col27 {width: 110px;}
      thead .col28 {width: 135px;}
      thead .col29 {width: 58px;}
      .col29 {text-align: right;}
      thead .col30 {width: 62px;}
      .col30 {text-align: right;}
      thead .col31 {width: 66px;}
      .col31 {text-align: right;}
      thead .col32 {width: 56px;}
      .col32 {text-align: right;}
      thead .col33 {width: 54px;}
      .col33 {text-align: right;}
      thead .col34 {width: 58px;}
      .col34 {text-align: right;}
      thead .col35 {width: 92px;}
      thead .col36 {width: 92px;}
      thead .col37 {width: 92px;}
      thead .col38 {width: 69px;}
      .col38 {text-align: right;}
      thead .col39 {width: 108px;}
      thead .col40 {width: 60px;}
      .col40 {text-align: right;}
      thead .col41 {width: 65px;}
      .col41 {text-align: right;}
      thead .col42 {width: 71px;}
      .col42 {text-align: right;}
      thead .col43 {width: 71px;}
      .col43 {text-align: right;}
      thead .col44 {width: 73px;}
      .col44 {text-align: right;}
      thead .col45 {width: 74px;}
      .col45 {text-align: right;}
      thead .col46 {width: 54px;}
      .col46 {text-align: right;}
      thead .col47 {width: 94px;}
      thead .col48 {width: 193px;}
      thead .col49 {width: 74px;}
      .col49 {text-align: right;}
      thead .col50 {width: 83px;}
      .col50 {text-align: right;}
      thead .col51 {width: 61px;}
      .col51 {text-align: right;}
      thead .col52 {width: 71px;}
      .col52 {text-align: right;}
      thead .col53 {width: 71px;}
      .col53 {text-align: right;}
      thead .col54 {width: 138px;}
      thead .col55 {width: 138px;}
      thead .col56 {width: 63px;}
      thead .col57 {width: 76px;}
      .col57 {text-align: right;}
      thead .col58 {width: 70px;}
      .col58 {text-align: right;}
      thead .col59 {width: 70px;}
      .col59 {text-align: right;}
      thead .col60 {width: 69px;}
      .col60 {text-align: right;}
      thead .col61 {width: 66px;}
      .col61 {text-align: right;}
      thead .col62 {width: 76px;}
      .col62 {text-align: right;}
      thead .col63 {width: 71px;}
      .col63 {text-align: right;}
      thead .col64 {width: 67px;}
      .col64 {text-align: right;}
      thead .col65 {width: 67px;}
      .col65 {text-align: right;}
      thead .col66 {width: 75px;}
      .col66 {text-align: right;}
      thead .col67 {width: 140px;}
      thead .col68 {width: 57px;}
      .col68 {text-align: right;}
      thead .col69 {width: 71px;}
      .col69 {text-align: right;}
      thead .col70 {width: 69px;}
      .col70 {text-align: right;}
      thead .col71 {width: 79px;}
      thead .col72 {width: 48px;}
      thead .col73 {width: 54px;}
      thead .col74 {width: 83px;}
      thead .col75 {width: 67px;}
      thead .col76 {width: 67px;}
      thead .col77 {width: 54px;}
      thead .col78 {width: 54px;}
      thead .col79 {width: 85px;}
      thead .col80 {width: 77px;}
      thead .col81 {width: 59px;}
      thead .col82 {width: 76px;}
      thead .col83 {width: 67px;}
      thead .col84 {width: 67px;}
    </style>
  </head>

  <body>

    <table caption="tbl_g08t1 (3 rows)">
      <thead>
        <tr>
          <th class="col0">shortl62</th>
          <th class="col1">carrno</th>
          <th class="col2">shortg04</th>
          <th class="col3">carrtype</th>
          <th class="col4">carrstat</th>
          <th class="col5">approved</th>
          <th class="col6">avail</th>
          <th class="col7">reserved</th>
          <th class="col8">carrctrl</th>
          <th class="col9">lock</th>
          <th class="col10">labeled</th>
          <th class="col11">mha</th>
          <th class="col12">rack</th>
          <th class="col13">horcoor</th>
          <th class="col14">vercoor</th>
          <th class="col15">ldct</th>
          <th class="col16">loctype</th>
          <th class="col17">stkquant</th>
          <th class="col18">stkzero</th>
          <th class="col19">delamo</th>
          <th class="col20">amooncr</th>
          <th class="col21">carrwght</th>
          <th class="col22">ldctwght</th>
          <th class="col23">carrvol</th>
          <th class="col24">regdate</th>
          <th class="col25">statdate</th>
          <th class="col26">stkdate</th>
          <th class="col27">freetxt1</th>
          <th class="col28">freetxt2</th>
          <th class="col29">minval</th>
          <th class="col30">maxval</th>
          <th class="col31">freerow</th>
          <th class="col32">depth</th>
          <th class="col33">width</th>
          <th class="col34">height</th>
          <th class="col35">bbdate</th>
          <th class="col36">ltdate</th>
          <th class="col37">lsdate</th>
          <th class="col38">lockcode</th>
          <th class="col39">allomark</th>
          <th class="col40">refg08</th>
          <th class="col41">ocarrno</th>
          <th class="col42">shortg00</th>
          <th class="col43">shortg02</th>
          <th class="col44">marktype</th>
          <th class="col45">checksum</th>
          <th class="col46">origin</th>
          <th class="col47">ecarrno</th>
          <th class="col48">g08fifo</th>
          <th class="col49">g08huqty</th>
          <th class="col50">shorto42</th>
          <th class="col51">icarrno</th>
          <th class="col52">shortg07</th>
          <th class="col53">shortg37</th>
          <th class="col54">g08pdate</th>
          <th class="col55">g08stkch</th>
          <th class="col56">origldct</th>
          <th class="col57">g08uwrap</th>
          <th class="col58">g08retur</th>
          <th class="col59">g08scale</th>
          <th class="col60">g08stort</th>
          <th class="col61">g08tqty</th>
          <th class="col62">g08badpu</th>
          <th class="col63">g08stqty</th>
          <th class="col64">firecode</th>
          <th class="col65">shortl66</th>
          <th class="col66">g08bcode</th>
          <th class="col67">ldctid</th>
          <th class="col68">ldctori</th>
          <th class="col69">g08crosc</th>
          <th class="col70">shortf04</th>
          <th class="col71">rundate</th>
          <th class="col72">txt8</th>
          <th class="col73">txt50</th>
          <th class="col74">txt71</th>
          <th class="col75">txt72</th>
          <th class="col76">txt73</th>
          <th class="col77">txt74</th>
          <th class="col78">txt75</th>
          <th class="col79">txt76</th>
          <th class="col80">txt97</th>
          <th class="col81">txt98</th>
          <th class="col82">txt132</th>
          <th class="col83">txt137</th>
          <th class="col84">txt155</th>
        </tr>
      </thead>
      <tbody>
        <tr>
          <td class="col0">165550</td>
          <td class="col1">33948712</td>
          <td class="col2">2249873</td>
          <td class="col3">0</td>
          <td class="col4">6</td>
          <td class="col5">1</td>
          <td class="col6">1</td>
          <td class="col7">0</td>
          <td class="col8">0</td>
          <td class="col9">0</td>
          <td class="col10">0</td>
          <td class="col11">B    </td>
          <td class="col12">011</td>
          <td class="col13">009</td>
          <td class="col14">008</td>
          <td class="col15">P01</td>
          <td class="col16">   </td>
          <td class="col17">6720</td>
          <td class="col18">0</td>
          <td class="col19">134400</td>
          <td class="col20">73600</td>
          <td class="col21">110.4</td>
          <td class="col22">0</td>
          <td class="col23">68.448</td>
          <td class="col24">2016-04-28 22:53:09</td>
          <td class="col25">2017-11-24 15:08:55</td>
          <td class="col26">2017-11-24 15:08:55</td>
          <td class="col27">                         </td>
          <td class="col28">L79CREXP                 </td>
          <td class="col29">0</td>
          <td class="col30">0</td>
          <td class="col31">7</td>
          <td class="col32">0</td>
          <td class="col33">0</td>
          <td class="col34">0</td>
          <td class="col35">                   </td>
          <td class="col36">                   </td>
          <td class="col37">                   </td>
          <td class="col38">0</td>
          <td class="col39">                    </td>
          <td class="col40">0</td>
          <td class="col41">0</td>
          <td class="col42">0</td>
          <td class="col43">0</td>
          <td class="col44">0</td>
          <td class="col45">0</td>
          <td class="col46">0</td>
          <td class="col47">J14122156</td>
          <td class="col48">0000165550.16042822:53          </td>
          <td class="col49">0</td>
          <td class="col50">0</td>
          <td class="col51">0</td>
          <td class="col52">0</td>
          <td class="col53">0</td>
          <td class="col54">2016-04-28 22:53:09</td>
          <td class="col55">2016-09-27 01:40:37</td>
          <td class="col56">   </td>
          <td class="col57">0</td>
          <td class="col58">0</td>
          <td class="col59">0</td>
          <td class="col60">0</td>
          <td class="col61">0</td>
          <td class="col62">0</td>
          <td class="col63">0</td>
          <td class="col64">0</td>
          <td class="col65">0</td>
          <td class="col66">0</td>
          <td class="col67">                                   </td>
          <td class="col68">0</td>
          <td class="col69">0</td>
          <td class="col70">0</td>
          <td class="col71">19-08-29</td>
          <td class="col72"></td>
          <td class="col73"></td>
          <td class="col74">20160427</td>
          <td class="col75">20160321</td>
          <td class="col76"></td>
          <td class="col77">J-SLS201609S</td>
          <td class="col78">03</td>
          <td class="col79">J14122156</td>
          <td class="col80"></td>
          <td class="col81"></td>
          <td class="col82">JGBR</td>
          <td class="col83"></td>
          <td class="col84"></td>
        </tr>
        <tr>
          <td class="col0">165551</td>
          <td class="col1">378320</td>
          <td class="col2">2401256</td>
          <td class="col3">0</td>
          <td class="col4">6</td>
          <td class="col5">1</td>
          <td class="col6">1</td>
          <td class="col7">0</td>
          <td class="col8">0</td>
          <td class="col9">0</td>
          <td class="col10">0</td>
          <td class="col11">A    </td>
          <td class="col12">011</td>
          <td class="col13">054</td>
          <td class="col14">011</td>
          <td class="col15">P01</td>
          <td class="col16">   </td>
          <td class="col17">4920</td>
          <td class="col18">0</td>
          <td class="col19">98400</td>
          <td class="col20">98400</td>
          <td class="col21">223.8</td>
          <td class="col22">0</td>
          <td class="col23">65.928</td>
          <td class="col24">2019-08-29 11:27:59</td>
          <td class="col25">2019-08-29 14:55:29</td>
          <td class="col26">2019-08-29 11:27:59</td>
          <td class="col27">                         </td>
          <td class="col28">TI39405                  </td>
          <td class="col29">0</td>
          <td class="col30">0</td>
          <td class="col31">5</td>
          <td class="col32">0</td>
          <td class="col33">0</td>
          <td class="col34">0</td>
          <td class="col35">                   </td>
          <td class="col36">                   </td>
          <td class="col37">                   </td>
          <td class="col38">0</td>
          <td class="col39">                    </td>
          <td class="col40">0</td>
          <td class="col41">0</td>
          <td class="col42">0</td>
          <td class="col43">0</td>
          <td class="col44">0</td>
          <td class="col45">0</td>
          <td class="col46">0</td>
          <td class="col47">29318284</td>
          <td class="col48">0000165551.19082911:27          </td>
          <td class="col49">0</td>
          <td class="col50">0</td>
          <td class="col51">0</td>
          <td class="col52">0</td>
          <td class="col53">0</td>
          <td class="col54">2019-08-29 11:27:59</td>
          <td class="col55">2019-08-29 11:27:59</td>
          <td class="col56">   </td>
          <td class="col57">0</td>
          <td class="col58">0</td>
          <td class="col59">0</td>
          <td class="col60">3</td>
          <td class="col61">0</td>
          <td class="col62">0</td>
          <td class="col63">0</td>
          <td class="col64">0</td>
          <td class="col65">0</td>
          <td class="col66">0</td>
          <td class="col67">                                   </td>
          <td class="col68">0</td>
          <td class="col69">0</td>
          <td class="col70">0</td>
          <td class="col71">19-08-29</td>
          <td class="col72"></td>
          <td class="col73"></td>
          <td class="col74">20190721</td>
          <td class="col75"></td>
          <td class="col76"></td>
          <td class="col77">V-SKFIT201925C</td>
          <td class="col78"></td>
          <td class="col79">J19070586</td>
          <td class="col80"></td>
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EN

回答 2

Stack Overflow用户

回答已采纳

发布于 2019-08-30 13:56:31

left join从左表返回所有行，从右表返回匹配行，因此，所有记录都分别从表的左侧更新。

使用INNER JOIN而不是LEFT JOIN，它将匹配表中的数据，并相应地更新表中匹配的记录：

代码语言：javascript
复制
UPDATE `61_LoadUnit`
    INNER JOIN `statistics`.`tbl_g08t1`
    ON `61_LoadUnit`.`StUnit` = `statistics`.`tbl_g08t1`.`ecarrno`
    SET `61_LoadUnit`.`carrno` = `statistics`.`tbl_g08t1`.`carrno`
    WHERE `61_LoadUnit`.`carrno` IN (NULL, 0);
票数 0
EN

Stack Overflow用户

发布于 2019-08-30 13:52:11

left join用于返回左表的所有行，即使与已连接的表没有匹配。

在您的示例中，如果有mo match，那么statistics.tbl_g08t1.carrno将是null，因此列61_LoadUnit.carrno将被更新为null，但在where子句中，我看到您希望在列为null (或0)时更新该列。

而且，如果该列是null，则此null永远不会成功，因为与null的任何比较都会返回null，而不是true。

那么，left join的意义是什么？

使其成为INNER JOIN，并在WHERE子句中使用正确的语法：

代码语言：javascript
复制
UPDATE `61_LoadUnit`
INNER JOIN `statistics`.`tbl_g08t1`
ON `61_LoadUnit`.`StUnit` = `statistics`.`tbl_g08t1`.`ecarrno`
SET `61_LoadUnit`.`carrno` = `statistics`.`tbl_g08t1`.`carrno`
WHERE `61_LoadUnit`.`carrno` IS NULL OR `61_LoadUnit`.`carrno` = 0

或

代码语言：javascript
复制
WHERE COALESCE(`61_LoadUnit`.`carrno`, 0) = 0
票数 1
EN
页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接：

https://stackoverflow.com/questions/57727011

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