合并同一表SQL中的行

Question

样本数据

id_type,seq_no,acct_name,_acct#,address
12345,67,jiimm,,167 s.40th st
12345,67,jiimm joe the 3rd,,167 s.40th st
12345,67,jiimm
12345,67,,0981_1,po box 1234
12345,80,Lee,,1234 street ave
12345,80,Lee
12345,80,,588_1,109 road st

码

SELECT `ID`_type,
       seq_no,
       MAX(`acct_name`) AS acct_name,
       MAX(`acct_#`) AS acct_#,
       address
FROM `test_table`
GROUP BY `ID`_type,
         seq_no;

---

我想基于id_type和seq_no合并行。 我正在使用max合并行，但是由于MAX acct＃，我正在覆盖所有现有地址和acct_names。

我的结果

id_type,seq_no.,acct_name,_acct#,address
12345,67,jiimm joe the 3rd,0981_1,167 s.40th st
12345,80,Lee,588_1,109 road st

• 输宝箱1234可获得67-
• 80失去1234大街，失去jiimm-

理想的结果

12345,80,Lee,588_1,109 road st
12345,80,Lee,588_1,1234 street ave    
12345,67,jiimm,0981_1,167 s.40th st
12345,67,jiimm,0981_1,po box 1234
12345,67,jiimm joe the 3rd,0981_1,167 s.40th st

Answer 1

这可以为您提供所需的信息，但请在上面的问题下方阅读我的评论/问题。 有一个模棱两可的“多选一排”的情况需要澄清。 在这种模棱两可的情况下，您暗示规则要求提供最小的非空白帐户名，此代码可以做到这一点，但是您可以看到它如何要求以一种方式处理帐户名，并以acct（＃）处理并解决其他问题。方式。 我认为您正朝着基于难以记住的规则提供结果的应用程序前进。 这样的时髦规则最终都会被报告为缺陷，即使您发布了上述处理规则。 因此，您可能需要增强上游捕获该数据的过程，以提供更严格的数据。

SQLFIDDLE链接 -简而言之，内部查询填充缺少的值，然后外部结果集提供不同的行。 我用不为空的空白值进行了测试。 我确实努力地添加了代码来处理空值，但是我没有使用空值对其进行测试，因此，如果可以使用生产环境，则建议对它进行测试。

select distinct * from (

  select     d.id_type, d.seq_no
            ,coalesce( nullif( acct_name, ''), min_acct_name ) as merged_acct_name
            ,coalesce( nullif( acct, ''),      max_acct      ) as merged_acct
            ,coalesce( nullif( address, ''),   max_address )   as merged_address
  from       test_table  d
  left join  ( select   id_type, seq_no
                       ,max( acct )      as max_acct
                       ,max( address )   as max_address
               from     test_table 
               group by id_type, seq_no
             ) as max_
        on   max_.id_type = d.id_type and max_.seq_no = d.seq_no
        and  (   coalesce( d.acct,'' )      = '' 
              or coalesce( d.address,'' )   = '' )
  left join  ( select   id_type, seq_no
                       ,min( acct_name ) as min_acct_name
               from     test_table 
               where    coalesce( acct_name, '' ) <> ''
               group by id_type, seq_no
             ) as min_
        on   min_.id_type = d.id_type and min_.seq_no = d.seq_no
        and  coalesce( d.acct_name,'' ) = ''
  ) as t

order by id_type, seq_no desc, merged_acct_name, merged_acct, merged_address

Answer 2

尝试这个：

select    distinct t1.id_type, t1.seq_no
          ,coalesce( t1.acct_name, t2.acct_name ) as merged_acct_name
          ,coalesce( t1.acct,      t2.acct      ) as merged_acct
          ,coalesce( t1.address,   t2.address )   as merged_address
from       test_table  t1
left join  test_table  t2
  on t1.id_type = t2.id_type
  and t1.seq_no = t2.seq_no
where concat(coalesce( t1.acct_name, t2.acct_name ) 
          ,coalesce( t1.acct,      t2.acct      )
          ,coalesce( t1.address,   t2.address )  ) is not null
order by t1.id_type, t1.seq_no;

要么：

select    distinct t1.id_type, t1.seq_no
          ,coalesce( t1.acct_name, t2.acct_name ) as merged_acct_name
          ,coalesce( t1.acct,      t3.acct      ) as merged_acct
          ,coalesce( t1.address,   t4.address )   as merged_address
from       test_table  t1
left join  test_table  t2
  on t1.id_type = t2.id_type
  and t1.seq_no = t2.seq_no
left join  test_table  t3
  on t1.id_type = t3.id_type
  and t1.seq_no = t3.seq_no
left join  test_table  t4
  on t1.id_type = t4.id_type
  and t1.seq_no = t4.seq_no
where concat(coalesce( t1.acct_name, t2.acct_name ) 
          ,coalesce( t1.acct,      t3.acct      )
          ,coalesce( t1.address,   t4.address )  ) is not null
order by t1.id_type, t1.seq_no;

SQL小提琴演示

Answer 3

SELECT
  D1.id_type
  , D1.seq_no
  , IFNULL(D1.acct_name, (SELECT MIN(acct_name) FROM data D WHERE D.id_type = D1.id_type AND D.seq_no = D1.seq_no)) t
  , IFNULL(D1.acct_no, (SELECT MAX(acct_no) FROM data D WHERE D.id_type = D1.id_type AND D.seq_no = D1.seq_no)) s
  , D1.address
FROM data D1
WHERE D1.address IS NOT NULL
ORDER BY id_type, seq_no DESC, acct_name
;

回报

| ID_TYPE | SEQ_NO |                 T |      S |         ADDRESS |
|---------|--------|-------------------|--------|-----------------|
|   12345 |     80 |               Lee |  588_1 |     109 road st |
|   12345 |     80 |               Lee |  588_1 | 1234 street ave |
|   12345 |     67 |             jiimm | 0981_1 |     po box 1234 |
|   12345 |     67 |             jiimm | 0981_1 |   167 s.40th st |
|   12345 |     67 | jiimm joe the 3rd | 0981_1 |   167 s.40th st |

除第三行和第四行的顺序外，这与您的预期输出一致。 但是，对于大量数据， MAX和MIN将越来越有限。

SQL小提琴