Sqlite-更改日期格式

有没有办法在Sqlite中更改此格式以使用select

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是否转换为正常的日期格式，例如（yyyy-mm-dd）？

SQLite不支持将月份名称或缩写转换为数字的任何功能。
这可以通过执行映射的CTE完成，然后连接到表：

WITH cte(month, month_name) AS (VALUES
  ('01', 'JAN'), ('02', 'FEB'), ('03', 'MAR'), ('04', 'APR'), ('05', 'MAY'), ('06', 'JUN'), 
  ('07', 'JUL'), ('08', 'AUG'), ('09', 'SEP'), ('10', 'OCT'), ('11', 'NOV'), ('12', 'DEC') 
)
SELECT SUBSTR(t.col, 1, 4) || '-' || c.month || '-' || printf('%02d', SUBSTR(t.col, 8)) date
FROM tablename t INNER JOIN cte c
ON t.col LIKE '%' || c.month_name || '%'
ORDER BY date;

WITH cte(month, month_name) AS (VALUES
  ('01', 'JAN'), ('02', 'FEB'), ('03', 'MAR'), ('04', 'APR'), ('05', 'MAY'), ('06', 'JUN'), 
  ('07', 'JUL'), ('08', 'AUG'), ('09', 'SEP'), ('10', 'OCT'), ('11', 'NOV'), ('12', 'DEC') 
)
UPDATE tablename AS t
SET col = SUBSTR(t.col, 1, 4) || '-' || 
          (SELECT c.month FROM cte c WHERE t.col LIKE '%' || c.month_name || '%') || '-' || 
          printf('%02d', SUBSTR(t.col, 8))

如果要更新表，请执行以下操作：

WITH cte(month, month_name) AS (VALUES
  ('01', 'JAN'), ('02', 'FEB'), ('03', 'MAR'), ('04', 'APR'), ('05', 'MAY'), ('06', 'JUN'), 
  ('07', 'JUL'), ('08', 'AUG'), ('09', 'SEP'), ('10', 'OCT'), ('11', 'NOV'), ('12', 'DEC') 
)
SELECT SUBSTR(t.col, 1, 4) || '-' || c.month || '-' || printf('%02d', SUBSTR(t.col, 8)) date
FROM tablename t INNER JOIN cte c
ON t.col LIKE '%' || c.month_name || '%'
ORDER BY date;

WITH cte(month, month_name) AS (VALUES
  ('01', 'JAN'), ('02', 'FEB'), ('03', 'MAR'), ('04', 'APR'), ('05', 'MAY'), ('06', 'JUN'), 
  ('07', 'JUL'), ('08', 'AUG'), ('09', 'SEP'), ('10', 'OCT'), ('11', 'NOV'), ('12', 'DEC') 
)
UPDATE tablename AS t
SET col = SUBSTR(t.col, 1, 4) || '-' || 
          (SELECT c.month FROM cte c WHERE t.col LIKE '%' || c.month_name || '%') || '-' || 
          printf('%02d', SUBSTR(t.col, 8))

将列的名称替换为列的名称。

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请参阅。

是完整月份还是三个字母的月份缩写？例如，是2021年1月10日还是2021年1月10日？3个字母的月份缩写