SQL 写不出来了 求救

Question

连接条件都没有？
不好意思   还有 一列 ID    ID是一样的 

Answer 1

连接条件都没有？
不好意思   还有 一列 ID    ID是一样的 
123和456是固定值？

Answer 2

      ID                A       B           C
      A001                                003
      A001       008   
      B001                                002
      B001        006
变成这样的       ID          A               B                     C
      A001                                        008
      A001  008      delete
      B001                                       006
      B001  006     delete

Answer 3

这效果？
SELECT * FROM
(select id,A,'delete' as B,C
FROM T
WHERE A IS NOT NULL
UNION ALL
SELECT NULL,NULL,A C
FROM T
WHERE A IS NOT NULL)
ORDER BY ID,A NULLS FIRST

Answer 4

UPDATE table_name a SET a.column_c=(SELECT b.column_a FROM  table_name b WHERE b.row_id=456)
WHERE a.row_id='123';
COMMIT;
UPDATE table_name a SET a.column_b='' WHERE a.row_id='456';
COMMIT;
这个意思？

Answer 5

      ID                A       B           C
      A001                                003
      A001       008   
      B001                                002
      B001        006
变成这样的       ID          A               B                     C
      A001                                        008
      A001  008      delete
      B001                                       006
      B001  006     delete
      ID                A       B           C
      A001                                003
      A001       008   
      B001                                002
      B001        006
变成这样的       ID          A               B                     C
      A001                                        008
      A001  008      delete
      B001                                       006
      B001  006     delete
      ID                A       B           C
      A001                                003
      A001       008   
      B001                                002
      B001        006
变成这样的       ID          A               B                     C
      A001                                        008
      A001  008      delete
      B001                                       006
      B001  006     delete
UPDATE TEST T
   SET T.C =
       (SELECT A
          FROM TEST T2
         WHERE T2.ID = T.ID
           AND T2.A IS NOT NULL)
 WHERE T.A IS NULL;
UPDATE TEST T
   SET T.B = 'DELETE'
 WHERE EXISTS (SELECT 1
          FROM TEST T2
         WHERE T2.C = T.A
           AND T2.ID = T.ID
           AND T2.A IS NULL)
   AND T.A IS NOT NULL;
COMMIT;