大家好，我有下表，它是由一个可怕的开发者设计的
该表包含USERS指纹及其USERID的数据。
来自（1,2,3,4,5,6,7,8,9,10,11,12,13,14）的FINGERID值 ISLOCKED并且ISDUPLICATE值为1或0 ...每个FINGERID都有图像存储在BLOB
Name Null Type
----------- -------- -------------
ROW_ID NUMBER
USERID NOT NULL NVARCHAR2(75)
TEMPLATE BLOB
FINGERID NOT NULL NVARCHAR2(20)
ISLOCKED NUMBER(3)
ISDUPLICATE NUMBER(3)
我希望以横向方式显示它，但是从2周开始没有运气......下面是我想要的选择语句结构
Name Null Type
----------------------- -------- -------------
USERID NOT NULL NVARCHAR2(75)
FINGERID_1 NVARCHAR2(20)
FINGERID_1_TEMPLATE BLOB
FINGERID_1_ISLOCKED NUMBER(3)
FINGERID_1_ISDUPLICATE NUMBER(3)
FINGERID_2 NVARCHAR2(20)
FINGERID_2_TEMPLATE BLOB
FINGERID_2_ISLOCKED NUMBER(3)
FINGERID_2_ISDUPLICATE NUMBER(3)
FINGERID_3 NVARCHAR2(20)
FINGERID_3_TEMPLATE BLOB
FINGERID_3_ISLOCKED NUMBER(3)
FINGERID_3_ISDUPLICATE NUMBER(3)
FINGERID_4 NVARCHAR2(20)
FINGERID_4_TEMPLATE BLOB
FINGERID_4_ISLOCKED NUMBER(3)
FINGERID_4_ISDUPLICATE NUMBER(3)
FINGERID_5 NVARCHAR2(20)
FINGERID_5_TEMPLATE BLOB
FINGERID_5_ISLOCKED NUMBER(3)
FINGERID_5_ISDUPLICATE NUMBER(3)
FINGERID_6 NVARCHAR2(20)
FINGERID_6_TEMPLATE BLOB
FINGERID_6_ISLOCKED NUMBER(3)
FINGERID_6_ISDUPLICATE NUMBER(3)
FINGERID_7 NVARCHAR2(20)
FINGERID_7_TEMPLATE BLOB
FINGERID_7_ISLOCKED NUMBER(3)
FINGERID_7_ISDUPLICATE NUMBER(3)
FINGERID_8 NVARCHAR2(20)
FINGERID_8_TEMPLATE BLOB
FINGERID_8_ISLOCKED NUMBER(3)
FINGERID_8_ISDUPLICATE NUMBER(3)
FINGERID_9 NVARCHAR2(20)
FINGERID_9_TEMPLATE BLOB
FINGERID_9_ISLOCKED NUMBER(3)
FINGERID_9_ISDUPLICATE NUMBER(3)
FINGERID_10 NVARCHAR2(20)
FINGERID_10_TEMPLATE BLOB
FINGERID_10_ISLOCKED NUMBER(3)
FINGERID_10_ISDUPLICATE NUMBER(3)
FINGERID_11 NVARCHAR2(20)
FINGERID_11_TEMPLATE BLOB
FINGERID_11_ISLOCKED NUMBER(3)
FINGERID_11_ISDUPLICATE NUMBER(3)
我尝试过使用此代码但没有运气，因为我无法显示TEMPLATE（BLOB），ISLOCKED，ISDUPLICATED
对于每个FINGERID，因为它不能与group by一起使用，pivot不是一个好选择，因为它需要聚合...我只是想显示数据是如何但是以水平方式为每个USERID。
`select
USERID,
SUM(case when FINGERID=1 then 1 END) as FINGERID_1,
SUM(case when FINGERID=2 then 2 END) as FINGERID_2,
SUM(case when FINGERID=3 then 3 END) as FINGERID_3,
SUM(case when FINGERID=4 then 4 END) as FINGERID_4,
SUM(case when FINGERID=5 then 5 END) as FINGERID_5,
SUM(case when FINGERID=6 then 6 END) as FINGERID_6,
SUM(case when FINGERID=7 then 7 END) as FINGERID_7,
SUM(case when FINGERID=8 then 8 END) as FINGERID_8,
SUM(case when FINGERID=9 then 9 END) as FINGERID_9,
SUM(case when FINGERID=10 then 10 END) as FINGERID_10,
SUM(case when FINGERID=11 then 11 END) as FINGERID_11,
SUM(case when FINGERID=12 then 12 END) as FINGERID_12,
SUM(case when FINGERID=13 then 13 END) as FINGERID_13,
SUM(case when FINGERID=14 then 14 END) as FINGERID_14
FROM TBLUSERFINGER group by userid;`
答案 0 :(得分：2)
这些数据类型确实存在问题。相反，您可以多次使用LEFT JOIN：
select u.userid,
f1.fingerid as fingerid_1,
f1.template as fingerid_1_template,
f1.islocked as fingerid_1_islocked,
f1.isduplicate as fingerid_1_isduplicate,
. . .
from (select distinct userid from TBLUSERFINGER) u left join
TBLUSERFINGER f1
on f1.userid = u.userid and f1.fingerid = 1 left join
TBLUSERFINGER f2
on f2.userid = u.userid and f2.fingerid = 2 left join
. . .
TBLUSERFINGER f14
on f14.userid = u.userid and f14.fingerid = 14 ;
答案 1 :(得分：0)
这是另一种方法。如果你的表非常大并且多次加入自身太慢，你可以将除了blob之外的所有东西都移出来，并将它存储在可以找到blob的地方。例如：
create table testx (
ROW_ID NUMBER,
USERID NVARCHAR2(75) NOT NULL,
TEMPLATE BLOB ,
FINGERID NVARCHAR2(20) NOT NULL,
ISLOCKED NUMBER(3) ,
ISDUPLICATE NUMBER(3)
);
create unique index testx_uidx on testx(userid, fingerid);
-- insert some test data
insert into testx values (1,'UID1',RAWTOHEX(UTL_RAW.CAST_TO_RAW('LOB1')),'1',1,0);
insert into testx values (2,'UID1',RAWTOHEX(UTL_RAW.CAST_TO_RAW('LOB2')),'2',1,0);
insert into testx values (3,'UID1',RAWTOHEX(UTL_RAW.CAST_TO_RAW('LOB3')),'3',0,0);
insert into testx values (4,'UID2',RAWTOHEX(UTL_RAW.CAST_TO_RAW('LOB1')),'1',1,0);
insert into testx values (5,'UID2',RAWTOHEX(UTL_RAW.CAST_TO_RAW('LOB2')),'2',1,0);
insert into testx values (6,'UID2',RAWTOHEX(UTL_RAW.CAST_TO_RAW('LOB3')),'3',0,0);
commit;
-- pivot out what we can, show rowid to blob data
select * from (
select userid, rowid as template_rowid, fingerid,islocked,isduplicate
from testx
)
pivot (
max(template_rowid) rowid_of_template, max(islocked) mislocked, max(isduplicate) misduplicate
for fingerid in ('1' fid1,'2' fid2,'3' fid3,'4' fid4,'5' fid5,'6' fid6,'7' fid7,'8' fid8,'9' fid9,'10' fid10,'11' fid11,'12' fid12,'13' fid13,'14' fid14)
);
输出：
USERID,FID1_ROWID_OF_TEMPLATE,FID1_MISLOCKED,FID1_MISDUPLICATE,FID2_ROWID_OF_TEMPLATE,FID2_MISLOCKED,FID2_MISDUPLICATE,FID3_ROWID_OF_TEMPLATE,FID3_MISLOCKED,FID3_MISDUPLICATE,FID4_ROWID_OF_TEMPLATE,FID4_MISLOCKED,FID4_MISDUPLICATE,FID5_ROWID_OF_TEMPLATE,FID5_MISLOCKED,FID5_MISDUPLICATE,FID6_ROWID_OF_TEMPLATE,FID6_MISLOCKED,FID6_MISDUPLICATE,FID7_ROWID_OF_TEMPLATE,FID7_MISLOCKED,FID7_MISDUPLICATE,FID8_ROWID_OF_TEMPLATE,FID8_MISLOCKED,FID8_MISDUPLICATE,FID9_ROWID_OF_TEMPLATE,FID9_MISLOCKED,FID9_MISDUPLICATE,FID10_ROWID_OF_TEMPLATE,FID10_MISLOCKED,FID10_MISDUPLICATE,FID11_ROWID_OF_TEMPLATE,FID11_MISLOCKED,FID11_MISDUPLICATE,FID12_ROWID_OF_TEMPLATE,FID12_MISLOCKED,FID12_MISDUPLICATE,FID13_ROWID_OF_TEMPLATE,FID13_MISLOCKED,FID13_MISDUPLICATE,FID14_ROWID_OF_TEMPLATE,FID14_MISLOCKED,FID14_MISDUPLICATE
"UID1","AAzWrKACUAAA1ffAAA",1,0,"AAzWrKACUAAA1ffAAB",1,0,"AAzWrKACUAAA1ffAAC",0,0,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
"UID2","AAzWrKACUAAA1ffAAD",1,0,"AAzWrKACUAAA1ffAAE",1,0,"AAzWrKACUAAA1ffAAF",0,0,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
然后，应用程序可以根据需要使用rowid快速执行查找（例如显示blob图像）。