redis集群支持交易吗？(does redis cluster support transactions ？)

 避免使用旧式连接。 因为enddate和startdate来自pettreatment表，并且您已经从中进行选择，所以您只需在where子句中指定条件即可。 无需选择。 
 
SELECT P.PETNAME,P.PETTYPE
FROM PETTREATMENT PT 
JOIN EXAMINATION E ON PT.EXAMNO = E.EXAMNO
JOIN PET P ON E.PETNO = P.PETNO
JOIN TREATMENT T ON PT.TREATNO = T.TREATNO 
WHERE TO_DATE(PT.ENDDATE,'DD-MON-YYYY') - TO_DATE(PT.STARTDATE,'DD-MON-YYYY') > 2
AND T.COST > 100
ORDER BY P.PETNAME;

Avoid using old-style joins. Because enddate and startdate come from pettreatment table, and you are already selecting from it, you can just specify the condition in the where clause. No need for a select.
 
SELECT P.PETNAME,P.PETTYPE
FROM PETTREATMENT PT 
JOIN EXAMINATION E ON PT.EXAMNO = E.EXAMNO
JOIN PET P ON E.PETNO = P.PETNO
JOIN TREATMENT T ON PT.TREATNO = T.TREATNO 
WHERE TO_DATE(PT.ENDDATE,'DD-MON-YYYY') - TO_DATE(PT.STARTDATE,'DD-MON-YYYY') > 2
AND T.COST > 100
ORDER BY P.PETNAME;