我试图在SQL中构建一些测试用例。问题是当我尝试使用左连接加入某个表时（如果我的理解是正确的，则应返回匹配和不匹配的行）当我尝试获取没有匹配ID的数据时，不会返回任何数据。这是代码：
select
E.ID_EVENEMENT,
t1.dateRecente as date_Star,
virage_c.no_contr,
t2.id as id_Univers,
t2.dateRecente as date_Univers,
t3.NUMERO_DOSSIER_STAR,
t3.dateRecente as Date_factcan,
t3.dateLimite,
t2.ID_PERSONNE_UNIVERS,
t1.ID_PERSONNE_STAR
FROM
STAR.EVENEMENT e
left join VIRAGE.CONTRAT virage_c
on e.NO_CONTRAT_OFFICIEL = to_char(virage_c.no_contr)
inner join
( SELECT
e.ID_EVENEMENT,
ep.ID_EVEN_INDIVIDU as ID_PERSONNE_STAR,
GREATEST( e.dt_creation,
NVL(e.DT_MODIF_STA_ELI, TO_DATE(1,'j')),
NVL(max(nt.dt_maj), TO_DATE(1,'j')),
NVL(max(ser.DT_CREATION), TO_DATE(1,'j')),
NVL(max(SER.DT_MAJ), TO_DATE(1,'j')),
NVL(max(aut.dt_transmis), TO_DATE(1,'j')),
NVL(max(AUT.DT_CREATION), TO_DATE(1,'j')) ) dateRecente
FROM
STAR.EVENEMENT e
left join STAR.Note nt
on e.ID_EVENEMENT = nt.ID_EVEN
left join STAR.SERVICE ser
on e.ID_EVENEMENT = ser.ID_EVEN
left join STAR.AUTORISATION aut
on ser.id_service = aut.id_service
left join STAR.DOCUMENT doc
on e.ID_EVENEMENT = doc.ID_EVENEMENT
left join STAR.ETAT ett
on e.ID_EVENEMENT = ett.ID_EVENEMENT
left join STAR.EVENEMENT_PARTICIPANT ep
on e.ID_EVENEMENT = ep.ID_EVENEMENT
GROUP BY
e.ID_EVENEMENT,
e.dt_creation,
e.DT_MODIF_STA_ELI,
ep.ID_EVEN_INDIVIDU ) t1
on t1.ID_EVENEMENT = E.ID_EVENEMENT
left JOIN
( SELECT
sf.STAREVENTNUMBER,
c.id,
par.ID as ID_PERSONNE_UNIVERS,
GREATEST( c.UPDATEDATE,
max(NVL(ca.UPDATEDATE, TO_DATE(1, 'J'))),
max(NVL(bo.UPDATEDATE, TO_DATE(1, 'J'))),
max(NVL(a.UPDATEDATE, TO_DATE(1, 'J'))),
max(NVL(p.UPDATEDATE, TO_DATE(1, 'J'))),
max(NVL(p.RELEASEDATE, TO_DATE(1, 'J'))),
max(NVL(p.PAYMENTDATE, TO_DATE(1, 'J'))) ) dateRecente
FROM
CV_CLAIMS_TRAVEL.STAR_FILE sf
join CV_CLAIMS_TRAVEL.CLAIM c
on sf.claimid = c.id
left join CV_CLAIMS_TRAVEL.BENEFIT_OPTION bo
on c.id = BO.CLAIMID
left join CV_CLAIMS_TRAVEL.ADJUDICATION a
on bo.id = a.BENEFITOPTIONID
left join CV_CLAIMS_TRAVEL.CLAIM_ACTIVITY ca
on c.id = CA.CLAIMID
left join CV_CLAIMS_TRAVEL.CLAIM_RELATIONSHIP cr
on c.id = CR.CLAIMID
left join CV_CLAIMS_TRAVEL.PAYEE pa
on cr.id = PA.CLAIMRELATIONSHIPID
left join CV_CLAIMS_TRAVEL.PAYMENT p
on pa.id = P.PAYEEID
left join CV_CLAIMS_TRAVEL.PARTY par
on par.ID = sf.PARTYID
WHERE
c.PRIMARYSTATUSLID in ('CLAIM_PRIMARY_STATUS:0000000003','CLAIM_PRIMARY_STATUS:0000000001')
OR ( c.PRIMARYSTATUSLID = 'CLAIM_PRIMARY_STATUS:0000000004'
AND bo.BENEFITOPTIONSTATUSLID in ('BENEFIT_OPTION_STATUS:0000000010',
'BENEFIT_OPTION_STATUS:0000000060',
'BENEFIT_OPTION_STATUS:0000000030')
)
group by
sf.STAREVENTNUMBER,
c.id,
c.UPDATEDATE,
par.ID ) t2
on e.ID_EVENEMENT = t2.STAREVENTNUMBER
LEFT JOIN
( SELECT DISTINCT
fact.NUMERO_DOSSIER_STAR,
GREATEST( to_date(fact.VSTDTCHG,'yyyymmdd'),
to_date(fact.VSTDICHK,'yyyymmdd'),
to_date(decode(fact.VSTDIFIN,0,19000101,
decode(substr(fact.VSTDIFIN,5),
'0230', substr(fact.VSTDIFIN,1,4)
|| '0301',fact.VSTDIFIN)),'yyyymmdd') ) DateRecente,
DECODE( virage_cont.id_cont,
null,add_months(sysdate,-7*12),
add_months(sysdate,-15*12)) dateLimite
FROM
FACTCAN.XC4DSAV fact
LEFT JOIN VIRAGE.CONTRAT virage_cont
on fact.VSTNOCNT_VIRAGE = virage_cont.NO_CONTR
where
fact.NUMERO_DOSSIER_STAR is not null ) t3
on e.ID_EVENEMENT = t3.NUMERO_DOSSIER_STAR
WHERE
t1.dateRecente < add_months(sysdate, -7*12)
AND t2.dateRecente < add_months(sysdate, -7*12)
AND virage_c.id_cont is null
AND t2.ID_PERSONNE_UNIVERS is not null
AND t1.ID_PERSONNE_STAR is null
AND t3.dateRecente < t3.dateLimite
FETCH
FIRST 1000 ROWS ONLY;
当我试图从任何一个事件中获取结果时 t1.ID_PERSONNE_STAR或t2.ID_PERSONNE_UNIVERS为空，当查询实际上应返回某些数据时，查询不返回任何内容。但是，这不是预期的工作。有什么想法吗？
答案 0 :(得分：0)
我更新了查询的可读性。另外，正如其他人所指出的，您必须小心WHERE子句。您可能遇到的问题是左边连接的T1，T2和T3的where子句...将这些子句移动到这些连接... ex
你有
的地方 left join (rest of the left-join subquery with alias ) t1
on t1.ID_EVENEMENT = E.ID_EVENEMENT
更改为
on t1.ID_EVENEMENT = E.ID_EVENEMENT
AND t1.dateRecente < add_months(sysdate, -7*12)
这样，日期要求是LEFT-JOIN的一部分。通过在WHERE子句中将其转换为INNER JOIN。
您可以在where子句部分保留T1“IS NULL”测试，因为您明确期望没有匹配的记录。
检查其他左连接的类似情况...将CRITERIA移至JOIN / ON子句并从WHERE中删除。 where子句应该对最终期望有“IS NULL”。