Snowflake Inner join with same table - snowflake-cloud-data-platform

Question

I am trying to bring this query in Snowflake. But, getting huge numbers with the last 3 inner joins which has same tables with different conditions.
select count(*) from table2; --5
select count(*) from table_3;--2824134
select count(*) from table1;--478015
Original Query:
select * from
from table1 d_tbl
inner join table2 r on r.number = d_tbl.number
inner join table_3 Zero on Zero.ID_I = r.id and Zero.time <= d_tbl.starttime and Zero.typeid in (7,19)
inner join table_3 first on first.ID_I = r.id and first.time <= Zero.time and first.typeid in (8,9)
inner join table_3 second on second.ID_I = r.id and second.time >= d_tbl.endtime and second.typeid in (8,9)
where d_tbl.mode = 0;
I tried breaking the queries into 3 parts.
create temp table tb1 as
select *
from table1 d_tbl
inner join table2 r on r.number = d_tbl.number ;
create temp table tb2 as
select ID_I , time as time as Zero_time,time as first_time,time as second_time
from table_3
where typeid in (8,9,7,19)
Note: saving the time column with different names for reference.
create temp table final_table as
select * from tb1 r
inner join tb2
on tb2.ID_I = r.id
where tb2.Zero_time <= r.starttime
and tb2.first_time <= Zero.time
and tb2.second_time >= r.endtime
Basically, I am trying to break the conditions in the joins to different parts.
This same logic has to be applied for different tables and do a union all for final table values.
Please help if this would work or let me know if this shall be handled with a better approach that executes faster.
TIA.

Answer 1

Try and convert following -
select * from
from table1 d_tbl
inner join table2 r on r.number = d_tbl.number
inner join table_3 Zero on Zero.ID_I = r.id
AND Zero.time <= d_tbl.starttime and Zero.typeid in (7,19)
inner join table_3 first on first.ID_I = r.id
AND first.time <= Zero.time and first.typeid in (8,9)
inner join table_3 second on second.ID_I = r.id
AND second.time >= d_tbl.endtime and second.typeid in (8,9)
where d_tbl.mode = 0;
To something like below -
select whatever-columns,
case when t3.time <= d_tbl.starttime
AND Zero.typeid in (7,19) then t3.time_1 end as zero_time,
case when t3.time <= zero_time
AND Zero.typeid in (8,9) then t3.time_1 end as first_time, --- snowflake allows to select/reference previous column
case when t3.time >= d_tbl.endtime
AND second.typeid in (8,9)then t3.time_1 end as second_time
from
table1 d_tbl
inner join table2 r on r.number = d_tbl.number
inner join table_3 t3 on t3.ID_I = r.id
where d_tbl.mode = 0;
This will help to reduce data-set being searched by avoiding multiple inner join on same table that has most records.