Hi!
I'm going to develop a commercial program with Firebird2.1, in Delphi7.
I want to know whether the following index is picked by the optimizer.
 

 
[The first question] 
CREATE INDEX IDX1 ON PROJECT(A)
CREATE INDEX IDX2 ON PROJECT(B)
CREATE INDEX IDX3 ON PROJECT(C)
CREATE INDEX IDX4 ON PROJECT(D)
 

 SELECT * PROJECT WHERE A=1 and B=2 and C=3 and D=4
 The optimizer would be choose the fastest way among table-full-scan and four 
indexs. Is this right?
 

 
[The second question] 
CREATE INDEX IDX1 ON PROJECT(A)
CREATE INDEX IDX2 ON PROJECT(B,C,D)
 SELECT * PROJECT WHERE A=1 and B=2 and C=3 and D=4
 The optimizer would be choose the fastest way among table-full-scan and two 
indexs. Is this right?
 

 

 [The third question] 
CREATE INDEX IDX ON PROJECT(B,C,D)
 SELECT * PROJECT WHERE A=1 and B=2 and C=3 and D=4
 The optimizer would be choose the fastest way among table-full-scan and IDX 
index. Is this right?
 

 Please tell me.
Thanks!

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