Mysql 在图表中添加零值

我构建了以下查询：

SELECT GVA14.COD_ZONA, Sum(GVA12.IMPORTE) AS SumOfIMPORTE
FROM GVA14 LEFT JOIN GVA12 
  ON GVA14.COD_CLIENT = GVA12.COD_CLIENT
WHERE Month(GVA12.FECHA_EMIS)=Month(curdate())
AND Year(GVA12.FECHA_EMIS)=Year(curdate())
GROUP BY GVA14.COD_ZONA;

SELECT GVA14.COD_ZONA, Coalesce(Sum(GVA12.IMPORTE), 0) AS SumOfIMPORTE
FROM GVA14 
LEFT JOIN GVA12 
  ON GVA14.COD_CLIENT = GVA12.COD_CLIENT
  AND Month(GVA12.FECHA_EMIS)=Month(curdate())
  AND Year(GVA12.FECHA_EMIS)=Year(curdate())
GROUP BY GVA14.COD_ZONA;

但是在

COD_ZONA

中还有其他的值我想显示。如果我去掉月份和年份的过滤器，它们就在那里了。这里有一个SQL提琴供感兴趣的人使用

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编辑1#

我现在有以下疑问：

SELECT GVA14.COD_ZONA, Sum(GVA12.IMPORTE) AS SumOfIMPORTE
FROM GVA14 LEFT JOIN GVA12 
  ON GVA14.COD_CLIENT = GVA12.COD_CLIENT
WHERE Month(GVA12.FECHA_EMIS)=Month(curdate())
AND Year(GVA12.FECHA_EMIS)=Year(curdate())
GROUP BY GVA14.COD_ZONA;

SELECT GVA14.COD_ZONA, Coalesce(Sum(GVA12.IMPORTE), 0) AS SumOfIMPORTE
FROM GVA14 
LEFT JOIN GVA12 
  ON GVA14.COD_CLIENT = GVA12.COD_CLIENT
  AND Month(GVA12.FECHA_EMIS)=Month(curdate())
  AND Year(GVA12.FECHA_EMIS)=Year(curdate())
GROUP BY GVA14.COD_ZONA;

但当我试着执行它时，它需要110秒，而我需要的程序在此之前会超时。我根据@Bluefeet的建议创建了一个索引，并将其命名为Zones，其中包括GVA14.COD_ZONA

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下一步怎么办？

将

WHERE

子句上的过滤器移动到

JOIN

条件。如果将筛选器保留在

WHERE

子句中，则查询的行为类似于

内部联接

，而不是

左联接

：

    SELECT GVA14.COD_ZONA
         , COALESCE(Sum(GVA12.IMPORTE),0) AS SumOfIMPORTE
      FROM GVA14 
      LEFT 
      JOIN GVA12 
        ON GVA14.COD_CLIENT = GVA12.COD_CLIENT
       AND Month(GVA12.FECHA_EMIS)=Month(curdate())
       AND Year(GVA12.FECHA_EMIS)=Year(curdate())
     GROUP 
        BY GVA14.COD_ZONA;

SELECT GVA14.COD_ZONA, Coalesce(Sum(GVA12.IMPORTE), 0) AS SumOfIMPORTE
FROM GVA14 
LEFT JOIN GVA12 
  ON GVA14.COD_CLIENT = GVA12.COD_CLIENT
  AND Month(GVA12.FECHA_EMIS)=Month(curdate())
  AND Year(GVA12.FECHA_EMIS)=Year(curdate())
GROUP BY GVA14.COD_ZONA;

看

结果:

| COD_ZONA | SUMOFIMPORTE |
---------------------------
|       01 |         3000 |
|       02 |         1000 |
|       03 |            0 |

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我通过在表上添加4个索引（不知道是否太多！）来解决这个问题。它工作了…

现在唯一的问题是执行需要很长时间，有时会导致超时。这可能是因为一个大的表吗？表上有索引吗？在Navicat中，执行需要110秒。那么长还是不长？我不认为有任何索引。我现在已经添加了一个索引，接下来呢？