Hi all
 

 Sorry for my late answer and thank you all for your input.  We experienced a 
large performance drop friday and it lasted until monday around 17.
 The place where we host our servers, had an update of some antivirus software 
which gave huge problems. 
 At first we suspected Firebird and the new server, so late sunday night I 
moved all back to the old server. Performance still very low. 
 

 And - Sorry to yhou guys how gace me an answer. I deleted them all by 
accident. 
 Sorry!
 

 That said - when we finally folund the reason, i got back to try to locate 
perfomance bottleneck on this one routine. 
 I located a BEFORE INSERT trigger, which causes this problem. 
 

 This one:
 

 CREATE TRIGGER WEB_UDSALG_SPR FOR VAREFRVSTR_DETAIL INACTIVE BEFORE INSERT 
POSITION 11 AS
 begin 
   Select 
     MAX(WEB_Udsalg_Spr), 
     MAX(WEB_Udsalg_Stk), 
     MAX(WEB_Udsalg_Type) 
 from VareFrvStr_Detail Where 
   VarePlu_ID=NEW.VarePlu_ID and 
   Afdeling_ID=NEW.Afdeling_ID 
 Into 
     NEW.WEB_Udsalg_Spr, 
     NEW.WEB_Udsalg_Stk, 
     NEW.WEB_Udsalg_Type;
 end
 

 Disabling this one and performance for this one routine increased back to 
normal. 
 

 

 If I try runing this query in DBW and look at the plan, its like this:
 

 

 PLAN (VAREFRVSTR_DETAIL INDEX (VAREFRVSTR_DETAIL_VNR, RDB$FOREIGN105))
 

 VAREFRVSTR_DETAIL_VNR: 0,00001301287 
 (Foreign key to field PLU_NR in table VARER with 76.863 rows)
 

 RDB$FOREIGN105: 0,01724137925
 This is the foreign key to AFDELINGSNUMMER in table AFDELING (containing 58 
records)
 

 I then did a SET STAT for the above 2 indeices. 
 Afterwards its like:
 

 RDB$FOREIGN105: 0,01724137925
 VAREFRVSTR_DETAIL_VNR: 0,00001300965
 

 This was the same problem. 
 

 

 

 Then I tested the PLAN on an older copy.
 

 It then said:
 

 PLAN (VAREFRVSTR_DETAIL INDEX (VAREFRVSTR_DETAIL_VNR))
 

 So on this server, where it works fast, the plan does not use the other 
ofreign key (RDB$FOREIGN105).
 

 This stat of the two indices on this old server is:
 

 RDB$FOREIGN105:  0,01724137925 (but not used).
 VAREFRVSTR_DETAIL_VNR: 0,00001332285
 

 So they are more or less alike. 
 On this server (my testserver) im running FB 2.5.3 SS.
 

 

 This means - this must be the reason for the performance drop.
 Right?
 

 

 And the solution is to drop the foreign key to table AFDELING, right?

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