关于sql查询

Question

我有下面的 sql 查询来插入表中的记录。问题是当没有用于选择查询的记录时，我仍然想要插入序列号、null、'3' 值的记录。当没有为选择查询找到记录时，不会插入任何内容。我该怎么做？

insert into test_details(seqnbr,trepid,type)
select '&seqid'
      ,REP_ID
      ,'3'
  FROM ref_details
 WHERE REP_ID >13;

Answer 1

一种方法是

insert into test_details(seqnbr,trpid,type)
select '&seqid',rep_id,'3' from ref_details where rep_id>13
union all select '&seqid',null,'3'
from dual where not exists(
select 1 from ref_details where rep_id>13)

Answer 2

Oracle 9i+：

如需填补空白，需create a list of sequencial values：

INSERT INTO TEST_DETAILS
  (seqnbr, trpid, type)
 SELECT '&seqid', rd.rep_id, '3'
     FROM (SELECT LEVEL + 13
             FROM DUAL
       CONNECT BY LEVEL <= 13) x
LEFT JOIN REF_DETAILS rd ON rd.rep_id = x.level
                        AND rd.rep_id > 13

...然后 LEFT JOIN 到可能有间隙的表。