Postgres 10

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select version();


version


PostgreSQL 10.12 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 8.3.1 20190507 (Red Hat 8.3.1-4), 64-bit


 create table table1(id int,loan_age int,  ori_upb int,  ori_rate numeric,  ltv numeric);
 
insert into table1 values( 1, 360, 1500,  4.5, 0.6 );
insert into table1 values(  2, 360, 2000,  3.8, 0.5 );
1 rows affected

1 rows affected


create table table2(id int,month varchar, cur_upb int, cur_rate numeric, status int);
 
insert into table2 values(1,'01',1400,4.5,0);
insert into table2 values(1,'02',1300,4.5,  0);
insert into table2 values(1,'03',1200,4.5,  1);
insert into table2 values(2,'01',2000,3.8,  0);
insert into table2 values(2,'02',1900,3.8,  0);
insert into table2 values(2,'03',1900,3.8,  1);
insert into table2 values(2,'04',1900,3.8,  2);
1 rows affected

1 rows affected

1 rows affected

1 rows affected

1 rows affected

1 rows affected

1 rows affected

 create table table3(id int,loan_age int,ori_upb int,ori_rate numeric,ltv numeric,  payoffmonth varchar, payoffupb int, payoffrate numeric, lastStatus int, modification date)
select distinct on (t1.id) t1.id, t1.loan_age, t1.ori_upb,t1.ori_rate,t1.ltv,t2.month,t2.cur_upb, t2.cur_rate, t2.status from table1 t1 inner join table2 t2 on t1.id=t2.id order by t1.id , t2.month desc


id
loan_age
ori_upb
ori_rate
ltv
month
cur_upb
cur_rate
status


1
360
1500
4.5
0.6
03
1200
4.5
1

2
360
2000
3.8
0.5
04
1900
3.8
2


create or replace function insert_values(table1 varchar, table2 varchar, table3 varchar)
returns int as $$
declare 
count_ int;
begin

execute format('insert into %I (id,  loan_age,  ori_upb,  ori_rate,  ltv,  payoffmonth, payoffupb,  payoffrate, lastStatus )
select distinct on (t1.id) t1.id, t1.loan_age, t1.ori_upb,t1.ori_rate,t1.ltv,t2.month,t2.cur_upb, t2.cur_rate, t2.status from %I t1 inner join %I t2 on t1.id=t2.id order by t1.id , t2.month desc',table3,table1,table2);
GET DIAGNOSTICS count_ = ROW_COUNT;
return count_;
end;
$$
language plpgsql
select * from insert_values('table1','table2','table3')


insert_values


2