Question

CREATE OR REPLACE FUNCTION j_f_sync_from_xml_2()
RETURNS boolean AS
$BODY$
DECLARE
myxml    xml;
datafile text := 'ABBATE_EMANUELE_Lvl1F2Va_20160418-1759_3.xml';
BEGIN

myxml := pg_read_file(datafile, 0, 100000000); 

CREATE TABLE public.james_2 AS
SELECT unnest(xpath('//@OPERATORE', t)) as Operatore, 
unnest(xpath('//@DATA', t)) as Data, unnest(xpath('//ObjectSelect/@NOME', 
t)) as Nome, unnest(xpath('//ObjectSelect/@TEMPO', t)) as Tempo, 
unnest(xpath('//ObjectSelect/@X', t)) as X, 
unnest(xpath('//ObjectSelect/@Y', t)) as Y,
unnest(xpath('//ObjectSelect/@Z', t)) as Z
FROM   unnest(xpath('/root/level', myxml)) x(t);
RETURN TRUE;
END;
$BODY$ language plpgsql;

此程序将列创建为XML类型。如何将XML类型转换为整数格式？我试过这段代码：

select  Tempo::text::int
from    james_2
cross join lateral
unnest(xpath('//ObjectSelect/@TEMPO', Tempo)) xp(T)

但是给我一个错误：＆lt;找不到

Answer 1

您正在尝试转换进入xpath调用的完整xml，而不是将别名为xp（T）的最终输出。我希望

select  T::text::int
from    james_2
cross join lateral
unnest(xpath('//ObjectSelect/@TEMPO', Tempo)) xp(T)

上班。 ::text::int演员是我在类似情况下使用它的正确理念。

如何将XML类型转换为整数？

1 个答案: