Aggregated count on left join result is incorrect after switching join order

select count(t1.ID)

from t1  -- 2

left join t2  on t2.ID = t1.ID -- 104

left join t3  on t3.ID = t1.ID -- 42

left join t4  on t4.ID = t1.ID -- 149

where t1.ID = 509583314; -- 71.565.312 != 2*104*42*149 = 1.301.664

select count(t1.ID)

from t1 -- 2

left join t2 on t2.ID = t1.ID -- 104

left join t4  on t4.ID = t1.ID -- 149          !!! switched t3 and t4 !!!

left join t3  on t3.ID = t1.ID -- 42

where t1.ID = 509583314; -- 1.301.664 = 2*104*149*42 = 1.301.664

select calSetTrace(1);

SELECT count(*)

from t1 -- 2

left join t2 on t2.ID = t1.ID -- 104

left join t3 on t3.ID = t1.ID -- 42

left join t4 on t4.ID = t1.ID -- 149

where t1.ID = 509583314; -- 71.565.312 != 2*104*42*149 = 1.301.664

select calGetTrace();

Desc Mode Table TableOID ReferencedColumns PIO LIO PBE Elapsed Rows

BPS PM t1 3311 (id) 0 3580 0 0.005 2

BPS PM t2 3314 (id) 0 520 0 0.016 0

HJS PM t2-t1 3314 - - - - ----- -

BPS PM t3 3318 (id) 0 664 0 0.022 0

HJS PM t3-t1 3318 - - - - ----- -

BPS PM t4 3321 (id) 0 4128 0 1.508 6655

HJS PM t4-t1 3321 - - - - ----- -

TAS UM - - - - - - 1.399 1

TNS UM - - - - - - 0.000 1

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select calSetTrace(1);

SELECT count(*)

from t1 -- 2

left join t2 on t2.ID = t1.ID -- 104

left join t4 on t4.ID = t1.ID -- 149 !!! switched t3 and t4 !!!

left join t3 on t3.ID = t1.ID -- 42

where t1.ID = 509583314; -- 1.301.664 = 2*104*149*42 = 1.301.664

select calGetTrace();

Desc Mode Table TableOID ReferencedColumns PIO LIO PBE Elapsed Rows

BPS PM t2 3314 (id) 0 392 0 0.020 0

HJS PM t2-t1 3314 - - - - ----- -

BPS PM t4 3321 (id) 0 2000 0 0.114 0

HJS PM t4-t1 3321 - - - - ----- -

BPS PM t3 3318 (id) 0 4193 0 0.211 4291957

BPS PM t1 3311 (id) 0 3580 0 0.018 2

HJS UM t1-t3 3311 - - - - ----- -

TAS UM - - - - - - 0.001 1

TNS UM - - - - - - 0.000 1