Postgres 15

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explain analyze verbose
select case when num%15=0 then 'FizzBuzz' 
            when num%3 =0 then 'Fizz'
            when num%5 =0 then 'Buzz'
            else num::text
       end
from generate_series(1,1e6,1) AS gen(num);

QUERY PLAN

Function Scan on pg_catalog.generate_series gen  (cost=0.00..30.00 rows=1000 width=32) (actual time=198.905..987.292 rows=1000000 loops=1)

  Output: CASE WHEN ((num % '15'::numeric) = '0'::numeric) THEN 'FizzBuzz'::text WHEN ((num % '3'::numeric) = '0'::numeric) THEN 'Fizz'::text WHEN ((num % '5'::numeric) = '0'::numeric) THEN 'Buzz'::text ELSE (num)::text END

  Function Call: generate_series('1'::numeric, '1000000'::numeric, '1'::numeric)

Planning Time: 0.093 ms

Execution Time: 1033.604 ms

EXPLAIN

explain analyze verbose
select coalesce(case when num%15=0 then 'FizzBuzz' end,
                case when num%3 =0 then 'Fizz'     end,
                case when num%5 =0 then 'Buzz'     end,
                num::text)
from generate_series(1,1e6,1) AS gen(num);

QUERY PLAN

Function Scan on pg_catalog.generate_series gen  (cost=0.00..30.00 rows=1000 width=32) (actual time=195.498..1067.345 rows=1000000 loops=1)

  Output: COALESCE(CASE WHEN ((num % '15'::numeric) = '0'::numeric) THEN 'FizzBuzz'::text ELSE NULL::text END, CASE WHEN ((num % '3'::numeric) = '0'::numeric) THEN 'Fizz'::text ELSE NULL::text END, CASE WHEN ((num % '5'::numeric) = '0'::numeric) THEN 'Buzz'::text ELSE NULL::text END, (num)::text)

  Function Call: generate_series('1'::numeric, '1000000'::numeric, '1'::numeric)

Planning Time: 0.071 ms

Execution Time: 1108.892 ms

EXPLAIN

explain analyze verbose
select (ARRAY[num::text,'Fizz','Buzz','FizzBuzz'])[ 1
                                                  +(num%3=0)::int
                                                  +2*(num%5=0)::int ]
from generate_series(1,1e6,1) AS gen(num);

QUERY PLAN

Function Scan on pg_catalog.generate_series gen  (cost=0.00..37.50 rows=1000 width=32) (actual time=190.536..1175.659 rows=1000000 loops=1)

  Output: (ARRAY[(num)::text, 'Fizz'::text, 'Buzz'::text, 'FizzBuzz'::text])[((1 + (((num % '3'::numeric) = '0'::numeric))::integer) + (2 * (((num % '5'::numeric) = '0'::numeric))::integer))]

  Function Call: generate_series('1'::numeric, '1000000'::numeric, '1'::numeric)

Planning Time: 0.058 ms

Execution Time: 1218.039 ms

EXPLAIN

explain analyze verbose
select coalesce( ('{Fizz,Buzz,FizzBuzz}'::text[])[(num%3=0)::int +2*(num%5=0)::int ] 
                , num::text)
from generate_series(1,1e6,1) AS gen(num);

QUERY PLAN

Function Scan on pg_catalog.generate_series gen  (cost=0.00..35.00 rows=1000 width=32) (actual time=256.534..1040.301 rows=1000000 loops=1)

  Output: COALESCE(('{Fizz,Buzz,FizzBuzz}'::text[])[((((num % '3'::numeric) = '0'::numeric))::integer + (2 * (((num % '5'::numeric) = '0'::numeric))::integer))], (num)::text)

  Function Call: generate_series('1'::numeric, '1000000'::numeric, '1'::numeric)

Planning Time: 0.203 ms

Execution Time: 1082.844 ms

EXPLAIN

explain analyze verbose
select coalesce( choices[(num%3=0)::int +2*(num%5=0)::int ] 
                , num::text)
from generate_series(1,1e6,1) AS gen(num), 
     (values ('{Fizz,Buzz,FizzBuzz}'::text[])) as a(choices);

QUERY PLAN

Function Scan on pg_catalog.generate_series gen  (cost=0.00..35.00 rows=1000 width=32) (actual time=200.242..974.311 rows=1000000 loops=1)

  Output: COALESCE(('{Fizz,Buzz,FizzBuzz}'::text[])[((((gen.num % '3'::numeric) = '0'::numeric))::integer + (2 * (((gen.num % '5'::numeric) = '0'::numeric))::integer))], (gen.num)::text)

  Function Call: generate_series('1'::numeric, '1000000'::numeric, '1'::numeric)

Planning Time: 0.083 ms

Execution Time: 1017.140 ms

EXPLAIN

explain analyze verbose
select coalesce(case when num%15=0 then 'FizzBuzz' end,
                case when num%3 =0 then 'Fizz'     end,
                case when num%5 =0 then 'Buzz'     end,
                num::text)
from generate_series(1,1e6,1) AS gen(num);

QUERY PLAN

Function Scan on pg_catalog.generate_series gen  (cost=0.00..30.00 rows=1000 width=32) (actual time=202.471..1065.202 rows=1000000 loops=1)

  Output: COALESCE(CASE WHEN ((num % '15'::numeric) = '0'::numeric) THEN 'FizzBuzz'::text ELSE NULL::text END, CASE WHEN ((num % '3'::numeric) = '0'::numeric) THEN 'Fizz'::text ELSE NULL::text END, CASE WHEN ((num % '5'::numeric) = '0'::numeric) THEN 'Buzz'::text ELSE NULL::text END, (num)::text)

  Function Call: generate_series('1'::numeric, '1000000'::numeric, '1'::numeric)

Planning Time: 0.061 ms

Execution Time: 1108.346 ms

EXPLAIN