無商不雅

◆2張資料表，要比對缺了哪幾筆

OM01 A

OM02 B

 

1、

select Table_1.a1 from (select a from OM01 A LEFT

JOIN OM02 B  ON A.OM1001 = B.OM2001)

WHERE B.OM2001 IS NULL

 

2、

SELECT A.OM1001  FROM OM01 A

WHERE A.OM1001 NOT IN (

SELECT B.OM2001 FROM OM02 B)

 

 

EX:

Table_1 a1

Table_6 a

 

SELECT a1 FROM Table_1

WHERE a1 NOT IN (

SELECT a FROM Table_6)

 

SELECT a FROM Table_6

WHERE a NOT IN (

SELECT a1 FROM Table_1

)