/*
...
Структара такая же как в начале предыдущего моего топика.
Строчек мало.
...
*/

select * from test.table1

 1 ; 10 
 2 ; 20 
 3 ; 30 
 4 ; 40 

select * from test.table2

 1 ; 1 ; 100 
 2 ; 1 ; 200 
 3 ; 1 ; 300 
 4 ; 2 ; 400 
 5 ; 2 ; 500 
 6 ; 2 ; 600 
 7 ; 4 ; 700 


select t2_id, t2_val from
       test.table2 inner join test.table1
              on t2_t1_id = t1_id
where t1_id =  2 ;

"Nested Loop  (cost=0.00..6.92 rows=1 width=8)"
"  ->  Seq Scan on table2  (cost=0.00..1.09 rows=1 width=12)"
"        Filter: (2 = t2_t1_id)"
"  ->  Index Scan using table1_pkey on table1  (cost=0.00..5.82 rows=1 width=4)"
"        Index Cond: (t1_id = 2)"

select t2_id, t2_val from
       test.table2 inner join test.table1
              on t2_t1_id = t1_id
where t1_id >  2  /* and t2_t1_id > 2 */;

"Hash Join  (cost=1.09..38.60 rows=3 width=8)"
"  Hash Cond: ("outer".t1_id = "inner".t2_t1_id)"
"  ->  Seq Scan on table1  (cost=0.00..34.25 rows=647 width=4)"
"        Filter: (t1_id > 2)"
"  ->  Hash  (cost=1.07..1.07 rows=7 width=12)"
"        ->  Seq Scan on table2  (cost=0.00..1.07 rows=7 width=12)"

select t2_id, t2_val from
       test.table2 inner join test.table1
              on t2_t1_id = t1_id
where t1_id >  2  and t2_t1_id >  2 ;

"Nested Loop  (cost=0.00..18.61 rows=2 width=8)"
"  ->  Seq Scan on table2  (cost=0.00..1.09 rows=3 width=12)"
"        Filter: (t2_t1_id > 2)"
"  ->  Index Scan using table1_pkey on table1  (cost=0.00..5.83 rows=1 width=4)"
"        Index Cond: ((table1.t1_id > 2) AND ("outer".t2_t1_id = table1.t1_id))"