JPA OneToOne映射

Question

I have a class InvitedTech .

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;

    ...
}

When I write a query to this table like this...

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

I get multiple select statements executed for each row that is in the invitedTech table. So for example I have 11 rows and after running that one query its like..

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=?

How would I fix this? If I write my own SQL I can do this in one statment using in keyword. I have tried different things like @BatchSize(size = 20) so that it fetches 20 records at a time, I have tried using @Fetch(FetchMode.JOIN) but all tries have not worked. Is there a I can change so only 1 query get executed?

If I remove the mappedBy from the annotations that removes the additional queries, but then I am unable to access those properties, because object does not know about the relationship.

Answer 1

为了避免出现n + 1问题，您可以尝试使用JOIN FETCH查询，如下所示（未经测试）：

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

Answer 2

You could use the @JoinFetch or @BatchFetch annotations on the flight and hotel objects if you would like your queries to fetch those relations in all queries performed.

Alternatively you could use a query hint to fetch those relations on a per-query basis.

Examples of all these are in this blog post .