在同一行中與同一網址對應的電話號碼分組

Question

在數據庫中，有一些相等的行，其中僅更改電話號碼。 我想將對應於相同網址的單行電話號碼分組，以獲得第二張表。 我想知道是否有一種方法可以在mysql中通過一個或多個查詢或通過另一種方法來執行此操作。 提前致謝

Database1
    Url    |Company Name| Address |  City |ZipCode|PHONE
www.aaa.com|         AAA|StreetAAA|CityAAA|  00000|0000000000
www.aaa.com|         AAA|StreetAAA|CityAAA|  00000|1111111111
www.aaa.com|         AAA|StreetAAA|CityAAA|  00000|2222222222
www.bbb.com|         BBB|StreetBBB|CityBBB|  11111|3333333333
www.ccc.com|         CCC|StreetCCC|CityCCC|  22222|4444444444
www.ccc.com|         CCC|StreetCCC|CityCCC|  22222|5555555555
www.ccc.com|         CCC|StreetCCC|CityCCC|  22222|6666666666
www.ddd.com|         DDD|StreetDDD|CityDDD|  33333|7777777777
www.ddd.com|         DDD|StreetDDD|CityDDD|  33333|8888888888
www.eee.com|         EEE|StreetEEE|CityEEE|  44444|9999999999

Final Database to generate:
    Url    |Company Name| Address |  City |ZipCode|  PHONE1  |  PHONE2  |  PHONE3
www.aaa.com|         AAA|StreetAAA|CityAAA|  00000|0000000000|1111111111|2222222222
www.bbb.com|         BBB|StreetBBB|CityBBB|  11111|3333333333|          |
www.ccc.com|         CCC|StreetCCC|CityCCC|  22222|4444444444|5555555555|6666666666
www.ddd.com|         DDD|StreetDDD|CityDDD|  33333|7777777777|8888888888|
www.eee.com|         EEE|StreetEEE|CityEEE|  44444|9999999999|          |

Answer 1

最簡單的解決方案是將所有電話放入逗號分隔的列表中：

select url, companyname, address, city, zipcode,
       group_concat(phone) as phones
from database1
group by url, companyname, address, city, zipcode;

但是，這並不是您想要的。 如果所有群組都有三個電話號碼，則以下內容更接近並可以使用：

select url, companyname, address, city, zipcode,
       substring_index(group_concat(phone), ',', 1) as phone1,
       substring_index(substring_index(group_concat(phone), ',', 2), ',', -1) as phone2,
       substring_index(group_concat(phone), ',', -1) as phone3
from database1
group by url, companyname, address, city, zipcode;

因此，以下解決了此問題：

select url, companyname, address, city, zipcode,
       (case when count(phone) >= 1
             then substring_index(group_concat(phone), ',', 1)
        end) as phone1,
       (case when count(phone) >= 2
             then substring_index(substring_index(group_concat(phone), ',', 2), ',', -1) 
        end) as phone2,
       (case when count(phone) >= 3
             then substring_index(group_concat(phone), ',', -1)
        end) as phone3
from database1
group by url, companyname, address, city, zipcode;