Howdy, Cedric .
Before analysing this problem of yours further, I 'd like you to kindly
clarify me some points, please
I have table following tables T0,T1,T2,T3, T1T2
with
-T0(id, fk_T1)
-T1(id )
-T2(id, fk_T3)
-T1T2(fk_T1,fk_T2)
-T3 (id)
The table T0 represents sets of T1 items.
The table T1 represents items.
The table T3 represents property types.
The table T2 represents represents property values of a specific type.
T0.id is not a primary key, is it?
For every T1 item of a T0 set I want to know if they do or do not have
T3 property types and if their values.
next comes view2 as
create view view2 as
select T2.fk_T3 as my_id
from T2,T1T2
where 1=1
and T1T2.fk_T1=23456
and T1T2.fk_T2=T2.id;
This will give me all properties types that the T1 item with id 23456 has.
let say this query gives me 4 rows.
T1T2 is an associative table between items and their property values, not
types, is this correct?
If so, I am not realizing why you say that this second view will give you
all property types. Didn't you mean property values?
Also, I am not reaching the point of the "1=1" thing. What is the propose
of it, exactly?
Isnt that condition always truth ? Maybe I am lacking some sql knowledge ...
Thanks in advance for advising me
Best,
Oliveiros
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