How do you use a multiple field unique key in a NOT IN statement?
I have a unique key that is going to be run through a NOT IN statement. How do you accomplish this?
SELECT DROPPER_ID, BEGIN_DT, END_DT
FROM VACATION_TEST
WHERE DROPPER_ID and BEGIN_DT and END_DT NOT IN (
SELECT DROPPER_I开发者_开发百科D, BEGIN_DT, END_DT
FROM VACATION_TEST
MINUS
SELECT REPORTER_VACATION.REPORTER, REPORTER_VACATION.BEGIN_DT, REPORTER_VACATION.END_DT
FROM REPORTER_VACATION, DROPPER
WHERE DROPPER.REPORTER = REPORTER_VACATION.REPORTER AND PROJECT_CD = 'INTL' );
use where not exists (select * from ... where a=.. and b=..)
Aside from NOT Exists
you can also you LEFT JOIN/ IS NULL
this assumes that all the joining fields are NOT NULL
SELECT vt.DROPPER_ID, vt.BEGIN_DT, vt.END_DT
FROM VACATION_TEST vt
LEFT JOIN (
SELECT DROPPER_ID, BEGIN_DT, END_DT
FROM VACATION_TEST
MINUS
SELECT REPORTER_VACATION.REPORTER, REPORTER_VACATION.BEGIN_DT, REPORTER_VACATION.END_DT
FROM REPORTER_VACATION, DROPPER
WHERE DROPPER.REPORTER = REPORTER_VACATION.REPORTER AND PROJECT_CD = 'INTL' ) ni
ON vt.DROPPER_ID = ni.DROPPER_ID
AND vt.BEGIN_DT =ni.BEGIN_DT
AND vt.END_DT = ni.END_DT
WHERE ni.DROPPER_ID is null
In oracle you can do something like
SELECT whatever
FROM table1
WHERE ( col1, col2 ) NOT IN
( SELECT expr1, expr2
FROM table2
)
/
Although some of the above solutions are probably more efficent. I usually avoid IN
and NOT IN
with subqueries. But it all depends on your situation and data model.
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