问题描述
我有两个桌子
- ERHAN_FLASH
- ERHAN_FLASH_NAME
ERHAN_FLASH:
COMPANY CONTENTNUMBER
TELEKOM 11146
TELEKOM 11146
TELEKOM 11146
TELEKOM 11146
TELEKOM 11146
TELEKOM 11147
TELEKOM 11147
TELEKOM 11147
TELEKOM 11147
TELEKOM 11147
ERHAN_FLASH_NAME:
EGIA_CONTENT_NAME EGI_CONTENT_CODE
Keyif Veren Sunum 510
Musteri Odakli icerik Yonetimi 2467
Temel Yonetim Becerileri 2469
Veritabani Dosyalama Sistemleri 2889
Sunum 2890
EGI_CONTENT_CODE等于CONTENTNUMBER
我需要像这样计数这些表
CONTENTNUMBER EGIA_CONTENT_NAME COUNT
11146 CONTENT1 146
11147 CONTENT2 42
12456 NULL 12
但ERHAN_FLASH_NAME EGI_CONTENT_CODE中的某些变量为空
我如何加入这两个表并计数
解决方法
您使用JOIN联接表,使用GROUP BY进行计数。
select EF.CONTENTNUMBER,EFN.EGIA_CONTENT_NAME,count(*) as COUNT
from ERHAN_FLASH EF
left join ERHAN_FLASH_NAME EFN
on EF.CONTENTNUMBER = EFN.EGI_CONTENT_CODE
group by EF.CONTENTNUMBER,EFN.EGIA_CONTENT_NAME
,
谢谢,但是此查询仅显示包含内容表,而EGIA_CONTENT_NAME不等于NULL示例:不显示
CONTENTNUMBER EGIA_CONTENT_NAME COUNT
12456 NULL 12
@Abra