I have a report that takes about 20 minutes to generate. It is generated
from 3 tables: according to image.
The report input parameter is a date range. So to generate it I select all
records in Table A and run them
in loop-for. For each record in Table A I make a query Table B join with
Table C where I filter the records through the date field and make the sum
of the value field.

Given this scenario, I would like your help in finding a solution that can
reduce the generation time of this report. System developed in PHP /
Laravel.

PostgreSQL
max_connections = 50
shared_buffers = 4GB
effective_cache_size = 12GB
maintenance_work_mem = 1GB
checkpoint_completion_target = 0.7
wal_buffers = 16MB
default_statistics_target = 100
random_page_cost = 4
effective_io_concurrency = 2
work_mem = 83886kB
min_wal_size = 1GB
max_wal_size = 2GB

Linux Server CentOS 7, Single Xeon 4-Core E3-1230 v5 3.4Ghz w / HT, 16GB
RAM.

I've already created indexes in the fields that are involved in the queries.
Database schema
[image: Untitled2.png]Report result
[image: Untitled.png]

--
Atenciosamente,

Evandro Abreu.
Engenheiro de Sistemas at STS Informática Ltda.
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