也许您可以使其功能（只是快速设置，请根据需要进行检查和更改）？

Perhaps you can make it a function (just a quick setup, please review and change as needed)?

CREATE OR REPLACE FUNCTION to_seconds(t text)
  RETURNS integer AS
$BODY$ 
DECLARE 
    hs INTEGER;
    ms INTEGER;
    s INTEGER;
BEGIN
    SELECT (EXTRACT( HOUR FROM  t::time) * 60*60) INTO hs; 
    SELECT (EXTRACT (MINUTES FROM t::time) * 60) INTO ms;
    SELECT (EXTRACT (SECONDS from t::time)) INTO s;
    SELECT (hs + ms + s) INTO s;
    RETURN s;
END;
$BODY$
  LANGUAGE 'plpgsql';

然后只需在查询中使用它即可：

Then just use it in your queries:

SELECT to_seconds('04:30:25');

返回值：

16225