Сomparing the approaches of Postgres and Mongo

• PostgreSQL version is 10
• Mongodb version is 4.0.3
• Records amount is 2 000 000.

Benchmark testing

For benchmarking testing was using Apache HTTP server benchmarking tool(ab).

1. SQL

Info
Concurrency Level	1
Time taken for tests	97.924 seconds
Complete requests	50
Failed requests	0
Total transferred	548350 bytes
HTML transferred	512250 bytes
Requests per second	0.51 [#/sec] (mean)
Time per request	1958.484 [ms] (mean)
Time per request	1958.484 [ms] (mean, across all concurrent requests)
Transfer rate	5.47 [Kbytes/sec] received

Connection Times (ms)	min	mean[+/-sd]	median	max
Connect	0	0	0.7	0
Processing	1615	1958	409.5	1779
Waiting	1615	1958	409.4	1779
Total	1615	1958	409.7	1779

Percentage of the requests served within a certain time (ms)
50%	1779
66%	2006
75%	2203
80%	2315
90%	2473
95%	2898
98%	3470
99%	3470
100%	3470 (longest request)

2. Materialized view

Info
Concurrency Level	1
Time taken for tests	56.721 seconds
Complete requests	50
Failed requests	0
Total transferred	545850 bytes
HTML transferred	509750 bytes
Requests per second	0.88 [#/sec] (mean)
Time per request	1134.415 [ms] (mean)
Time per request	1134.415 [ms] (mean, across all concurrent requests)
Transfer rate	9.40 [Kbytes/sec] received

Connection Times (ms)	min	mean[+/-sd]	median	max
Connect	0	0	0.0	0
Processing	985	1134	188.6	1091
Waiting	984	1134	188.6	1091
Total	985	1134	188.6	1091

Percentage of the requests served within a certain time (ms)
50%	1091
66%	1134
75%	1173
80%	1210
90%	1357
95%	1374
98%	2228
99%	2228
100%	2228 (longest request)

3. Mongo: Aggregation Framework

Info
Concurrency Level	1
Time taken for tests	161.855 seconds
Complete requests	50
Failed requests	0
Total transferred	548350 bytes
HTML transferred	512250 bytes
Requests per second	0.31 [#/sec] (mean)
Time per request	3237.104 [ms] (mean)
Time per request	3237.104 [ms] (mean, across all concurrent requests)
Transfer rate	3.31 [Kbytes/sec] received

Connection Times (ms)	min	mean[+/-sd]	median	max
Connect	0	0	0.0	0
Processing	2728	3237	490.4	3093
Waiting	2728	3237	490.4	3093
Total	2728	3237	490.4	3093

Percentage of the requests served within a certain time (ms)
50%	3093
66%	3225
75%	3439
80%	3674
90%	3878
95%	3910
98%	5445
99%	5445
100%	5445 (longest request)

4. Mongo: MapReduce

Info
Concurrency Level	1
Time taken for tests	682.079 seconds
Complete requests	50
Failed requests	0
Total transferred	548400 bytes
HTML transferred	512250 bytes
Requests per second	0.07 [#/sec] (mean)
Time per request	13641.582 [ms] (mean)
Time per request	13641.582 [ms] (mean, across all concurrent requests)
Transfer rate	0.79 [Kbytes/sec] received

Connection Times (ms)	min	mean[+/-sd]	median	max
Connect	0	0	0.0	0
Processing	12000	13641	1088.1	13569
Waiting	12000	13641	1088.1	13569
Total	12000	13642	1088.1	13569

Percentage of the requests served within a certain time (ms)
50	13569
66	14030
75	14375
80	14703
90	15303
95	15420
98	16598
99	16598