在两列之间获取不常见的 ID

Question

我有两个 table，如果 table 中不存在任何一个 ID，我需要获取它 2. 我尝试了查询，但没有给出正确的结果。欢迎推荐。

TABLE 1

TABLE 2

输出应该是：因为发布 ID 和购买 ID 不在两列中。

QUERY 已尝试：

SELECT T1_ID 
FROM T1 LEFT OUTER JOIN T2
ON t1.RELEASEID=t2.RELEASEID
LEFT OUTER JOIN T2 t3
ON t1.PURCHASEID=t3.PURCHASEID
WHERE IFNULL(T2.RELEASEID,'') ='' OR IFNULL(T3.PURCHASEID,'')=''

Answer 1

您可以按如下方式使用NOT EXISTS：

select * from t1
where not exists (select 1 from t2
where t1.releaseid =t2.releaseid or t1.purchaseid =t2.purchaseid)

您还可以使用LEFT JOIN如下：

select t1.*
  from t1 left join t2
    on t1.releaseid =t2.releaseid or t1.purchaseid =t2.purchaseid
 where t2.t2_id is null

Answer 2

一种方法是not exists:

select t1.*
from t1
where not exists (select 1
                  from t2
                  where t2.releaseid = t1.releaseid
                 ) and
      not exists (select 1
                  from t2
                  where t2.purchaseid = t1.purchaseid
                 );

无论 ? 是否真的是一个字符串或应该表示 NULL.

，这都应该有效

注意：这可以利用 t2(releaseid) 和 t2(purchaseid) 上的索引，这可以大大提高更大数据的性能。

Answer 3

我想你想要：

select t1.*
from table1 t1
where 
    (t1.release_id = '?' and t2.purchase_id = '?')
    or not exists (
        select 1
        from table2 t2
        where t1.release_id in ('?', t2.release_id)
          and t1.purchase_id in ('?', t2.purchase_id)
)

如果问号应该代表 null 值，您可以将 = '?' 的所有实例替换为 is null。

Answer 4

请试试这个，如果有效请告诉我。

SELECT * FROM TABLE1 WHERE NOT EXISTS (SELECT '1' FROM TABLE2 WHERE TABLE1 .RELEASEID=TABLE2.RELEASEID OR  TABLE1 .PURCHASEID=TABLE2.PURCHASEID);

在两列之间获取不常见的 ID

Fectch uncommon ID between two columns

sql

oracle

oracle11g