JPA OneToOne mappedBy

Question

我有一个InvitedTech类。

public class InvitedTech{
    ...
    @OneToOne(mappedBy="invitedTech", cascade = CascadeType.ALL, fetch=FetchType.LAZY)
    public Flight flight;

    @OneToOne(mappedBy="invitedTech", cascade = CascadeType.ALL, fetch=FetchType.LAZY)
    public Hotel hotel;

    ...
}

当我像这样写一个查询到这个表时...

List<InvitedTech> invT = JPA.em().createQuery("SELECT inv from InvitedTech inv").getResultList();

我为invitedTech表中的每一行执行了多个select语句。例如，我有11行，在运行该查询之后，结果类似于..

13:09:26,350 DEBUG ~ select invitedtec0_.id as id184_, invitedtec0_.comments as comments184_, invitedtec0_.confirmedBy as confirm11_184_, invitedtec0_.confirmedDate as confirme3_184_, invitedtec0_.contractor as contractor184_, invitedtec0_.flightNeeded as flightNe4_184_, invitedtec0_.hotelNeeded as hotelNee5_184_, invitedtec0_.inviteDate as inviteDate184_, invitedtec0_.method as method184_, invitedtec0_.payRate as payRate184_, invitedtec0_.paymentItem_id as payment13_184_, invitedtec0_.replyDate as replyDate184_, invitedtec0_.status as status184_, invitedtec0_.techRequirement as techReq14_184_ from InvitedTech invitedtec0_
13:09:26,354 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,355 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,357 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,357 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,358 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,359 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,360 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,361 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,362 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,362 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,363 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,364 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,364 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,365 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,366 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,367 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,367 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,368 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,370 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,371 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?
13:09:26,372 DEBUG ~ select flight0_.id as id156_1_, flight0_.airline as airline156_1_, flight0_.confirmationNumber as confirma3_156_1_, flight0_.departure as departure156_1_, flight0_.flightNumber as flightNu5_156_1_, flight0_.invitedTechId as invitedT7_156_1_, flight0_.terminal as terminal156_1_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_ from Flight flight0_ inner join InvitedTech invitedtec1_ on flight0_.invitedTechId=invitedtec1_.id where flight0_.invitedTechId=?
13:09:26,372 DEBUG ~ select hotel0_.id as id189_2_, hotel0_.address as address189_2_, hotel0_.checkinTime as checkinT3_189_2_, hotel0_.confirmationNumber as confirma4_189_2_, hotel0_.invitedTechId as invitedT7_189_2_, hotel0_.name as name189_2_, hotel0_.phone as phone189_2_, invitedtec1_.id as id184_0_, invitedtec1_.comments as comments184_0_, invitedtec1_.confirmedBy as confirm11_184_0_, invitedtec1_.confirmedDate as confirme3_184_0_, invitedtec1_.contractor as contractor184_0_, invitedtec1_.flightNeeded as flightNe4_184_0_, invitedtec1_.hotelNeeded as hotelNee5_184_0_, invitedtec1_.inviteDate as inviteDate184_0_, invitedtec1_.method as method184_0_, invitedtec1_.payRate as payRate184_0_, invitedtec1_.paymentItem_id as payment13_184_0_, invitedtec1_.replyDate as replyDate184_0_, invitedtec1_.status as status184_0_, invitedtec1_.techRequirement as techReq14_184_0_, flight2_.id as id156_1_, flight2_.airline as airline156_1_, flight2_.confirmationNumber as confirma3_156_1_, flight2_.departure as departure156_1_, flight2_.flightNumber as flightNu5_156_1_, flight2_.invitedTechId as invitedT7_156_1_, flight2_.terminal as terminal156_1_ from Hotel hotel0_ inner join InvitedTech invitedtec1_ on hotel0_.invitedTechId=invitedtec1_.id left outer join Flight flight2_ on invitedtec1_.id=flight2_.invitedTechId where hotel0_.invitedTechId=?

我该怎么解决这个问题？如果我编写自己的SQL，我可以使用in关键字在一条语句中完成这项工作。我已经尝试了不同的方法，比如@BatchSize(size = 20)，它一次可以获取20条记录，我也尝试过使用@Fetch(FetchMode.JOIN)，但所有的尝试都不起作用。是否有一个I可以更改，以便只执行一个查询？

如果我从删除附加查询的注释中删除mappedBy，但随后我无法访问这些属性，因为object不知道该关系。

Answer 1

为了避免n+1问题，您可以尝试像这样使用JOIN FETCH查询(未经测试)：

SELECT inv from InvitedTech inv LEFT JOIN FETCH inv.flight LEFT JOIN FETCH inv.hotel

Answer 2

如果希望查询在执行的所有查询中获取这些关系，则可以在flight和hotel对象上使用@JoinFetch或@BatchFetch注释。

或者，您可以使用查询提示在每个查询的基础上获取这些关系。

所有这些的例子都是in this blog post。