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PostgreSQL:complete los valores NULL en la consulta de la serie de tiempo con el valor anterior

Encontré el siguiente método más fácil:

Cree la muestra de datos dada:

WITH example (date,close) AS 
(VALUES 
    ('12:00:00',3),
    ('12:00:01',4),
    ('12:00:02',5),
    ('12:00:03',NULL),
    ('12:00:04',NULL), 
    ('12:00:05',3)
) 
SELECT * INTO temporary table market_summary FROM example;

Consulta para completar valores NULL con el valor anterior

select 
    date, 
    close, 
    first_value(close) over (partition by grp_close) as corrected_close
from (
      select date, close,
             sum(case when close is not null then 1 end) over (order by date) as grp_close
      from   market_summary
) t

Volver

date      | close | corrected_close
-----------------------------------
12:00:00  | 3     | 3
12:01:00  | 4     | 4
12:02:00  | 5     | 5
12:03:00  | NULL  | 5
12:04:00  | NULL  | 5
12:05:00  | 3     | 3
  • cerrar:valor existente
  • corrected_close:valor corregido