Mysql sql-排除空值

如何删除那些非值列？ 这是我的疑问：

SELECT CASE 
            WHEN region = 'CENTRAL'
               THEN 'Central' 
             WHEN region = 'EASTERN'
               THEN 'Eastern'   
               WHEN region = 'NORTHERN'
               THEN 'Northern' 
             WHEN region = 'SOUTHERN'
               THEN 'Southtern'               
  END as Peninsular , 
             case 
             WHEN region = 'BINTULU'
               THEN 'BINTULU' 
             WHEN region = 'KUCHING'
               THEN 'Kuching'   
               WHEN region = 'SIBU'
               THEN 'Sibu' 
   END as Sarawak,
            case 
             WHEN region = 'KOTA KINABALU'
               THEN 'KOTA KINABALU' 
             WHEN region = 'LAHAD DATU'
               THEN 'LAHAD DATU'  
               WHEN region = 'SANDAKAN'
               THEN 'SANDAKAN'
               WHEN region = 'TAWAU'
               THEN 'TAWAU'
   END as Sabah,
   region  
FROM locinvaisle
group by region

---

如果区域是您的关键值，则添加

...
FROM locinvaisle
WHERE region IS NOT NULL
...

取决于区域是空还是空。

尝试此查询

添加这一行

where region is not null AND region != ''

在表名之后

SELECT 
    CASE 
       WHEN region = 'CENTRAL' THEN 'Central' 
       WHEN region = 'EASTERN' THEN 'Eastern'   
       WHEN region = 'NORTHERN' THEN 'Northern' 
       WHEN region = 'SOUTHERN' THEN 'Southern'               
    END as Peninsular , 
    CASE
       WHEN region = 'BINTULU' THEN 'BINTULU' 
       WHEN region = 'KUCHING' THEN 'Kuching'   
       WHEN region = 'SIBU' THEN 'Sibu' 
    END as Sarawak,
    CASE
       WHEN region = 'KOTA KINABALU' THEN 'KOTA KINABALU' 
       WHEN region = 'LAHAD DATU' THEN 'LAHAD DATU'  
       WHEN region = 'SANDAKAN' THEN 'SANDAKAN'
       WHEN region = 'TAWAU' THEN 'TAWAU'
    END as Sabah,
    region  
FROM 
    locinvaisle 
WHERE
    region IS NOT NULL AND region != ''
GROUP BY
    region

添加一个条件

---

从Locinavaile何处区域！=''

您能发布您的模式并在问题中添加示例数据吗？您的预期输出是什么？我想不出在这里做什么。我希望输出只显示填充的列，但似乎有些值仍然存在，但隐藏/空，正如您在“Region”中看到的，行是实际值。您显示的每一行都有空列。你甚至自己创造了这些。例如，宾图鲁地区没有沙巴。那么，您希望如何抑制非填充列？是否改为显示类似“空”的文本？还是你根本不想展示宾图鲁街？请出示您的预期结果。（请不要显示图像，而是将表格数据粘贴为文本。）

SELECT 
    CASE 
       WHEN region = 'CENTRAL' THEN 'Central' 
       WHEN region = 'EASTERN' THEN 'Eastern'   
       WHEN region = 'NORTHERN' THEN 'Northern' 
       WHEN region = 'SOUTHERN' THEN 'Southern'               
    END as Peninsular , 
    CASE
       WHEN region = 'BINTULU' THEN 'BINTULU' 
       WHEN region = 'KUCHING' THEN 'Kuching'   
       WHEN region = 'SIBU' THEN 'Sibu' 
    END as Sarawak,
    CASE
       WHEN region = 'KOTA KINABALU' THEN 'KOTA KINABALU' 
       WHEN region = 'LAHAD DATU' THEN 'LAHAD DATU'  
       WHEN region = 'SANDAKAN' THEN 'SANDAKAN'
       WHEN region = 'TAWAU' THEN 'TAWAU'
    END as Sabah,
    region  
FROM 
    locinvaisle 
WHERE
    region IS NOT NULL AND region != ''
GROUP BY
    region