explain analyze select * from log_entries where user_name='john_doe' order by timestamp desc limit 100 offset 0;
                                                                            QUERY PLAN                                                                            
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 Limit  (cost=0.00..235.47 rows=100 width=175) (actual time=0.945..5.858 rows=100 loops=1)
   ->  Index Scan Backward using timestamp_log_entries_key on log_entries  (cost=0.00..39093.47 rows=16602 width=175) (actual time=0.938..5.622 rows=100 loops=1)
         Filter: ((user_name)::text = 'john_doe'::text)
 Total runtime: 6.175 ms
(4 rows)



explain analyze select * from log_entries where user_name like '%john_doe%' limit 100 offset 0;
                                                    QUERY PLAN                                                    
------------------------------------------------------------------------------------------------------------------
 Limit  (cost=0.00..8250.17 rows=1 width=175) (actual time=0.495..3.364 rows=100 loops=1)
   ->  Seq Scan on log_entries  (cost=0.00..8250.17 rows=1 width=175) (actual time=0.486..3.138 rows=100 loops=1)
         Filter: ((user_name)::text ~~ '%john_doe%'::text)
 Total runtime: 3.657 ms
(4 rows)



explain analyze select * from log_entries where user_name like '%john_doe%' order by timestamp desc limit 100 offset 0;
                                                         QUERY PLAN                                                          
-----------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=8250.18..8250.19 rows=1 width=175) (actual time=1880.358..1880.910 rows=100 loops=1)
   ->  Sort  (cost=8250.18..8250.19 rows=1 width=175) (actual time=1880.345..1880.701 rows=100 loops=1)
         Sort Key: "timestamp"
         ->  Seq Scan on log_entries  (cost=0.00..8250.17 rows=1 width=175) (actual time=0.432..1051.036 rows=15481 loops=1)
               Filter: ((user_name)::text ~~ '%john_doe%'::text)
 Total runtime: 1887.071 ms
(6 rows)