[sqlite] Multiple Column index

[Michele Pradella]

Hi all, I have a question about using index with multiple column.
Take this test case
CREATE TABLE test (DateTime BIGINT,CarPlate VARCHAR(255));
CREATE INDEX indexA ON test(DateTime);
CREATE INDEX indexB ON test(CarPlate);
CREATE INDEX indexAB ON test(DateTime,CarPlate);

now if you do
[1] -> EXLPAIN QUERY PLAN SELECT * FROM test WHERE (DateTime=0) AND 
(CarPlate='AA000BB')

you obtain:
0|0|0|SEARCH TABLE test USING COVERING INDEX indexAB (DateTime=? AND 
CarPlate=?)
So it's good.

if you do
EXLPAIN QUERY PLAN SELECT * FROM test WHERE 
(DateTime>1)AND(DateTime<100) AND (CarPlate = 'AA000BB');
0|0|0|SEARCH TABLE test USING INDEX indexB (CarPlate=?)
So is used only the indexB not the index for DateTime, and if you force 
it indexAB
0|0|0|SEARCH TABLE test USING COVERING INDEX indexAB (DateTime>? AND 
DateTime<?)
so it used only for DateTime.

Do you think Is there a way to use indexAB (or using both index 
combining two select) to cover both condition (DateTime>X AND 
DateTime<Y  and CarPlate = 'something' )? multicolumn index can be used 
only for [1] queries?