使用 Xmltable postgres 在 xml 的临时 table 中插入值

Question

我正在尝试将 xml 个节点作为参数传递并从中提取值并将它们插入到 table 中。如果我传递整个 xml 节点，我可以这样做，但如果我尝试通过变量传递它，我将面临语法错误。由于我将拥有需要解析的动态 xml，因此我必须仅通过变量传递它。我在下面提供了我要实现的目标的简化版本。我收到语法错误 'syntax error at or near "xmlvalue"'

CREATE TEMPORARY TABLE SAMPLE(Id text,Author text,Title text);
xmlvalue text := '<Book><Id>1</Id><Author>Subhrendu</Author><Title>Postgre</Title></Book>';
with data as ( 
select xmlvalue::xml val)
--select '<Book><Id>1</Id><Author>Subhrendu</Author><Title>Postgre</Title></Book>'::xml val)
INSERT INTO SAMPLE(Id, Author,Title)
SELECT Id, Author,Title 
FROM   data x, 
XMLTABLE('/Book' 
PASSING val 
COLUMNS  
Id    text  PATH 'Id', 
Author text  PATH 'Author', 
Title text PATH 'Title' )   
; 
select * from sample

编辑 1：正如建议的那样，我现在尝试将上面的代码包装在一个函数中，因为我们不能在 procedures/functions.

之外使用变量

create or replace function xml()
returns table(Id text,Author Text,Title Text)
as $$
declare
xmlvalue text := '<Book><Id>1</Id><Author>Subhrendu</Author><Title>Postgre</Title></Book>';
begin
CREATE TEMPORARY TABLE SAMPLE(Id text,Author text,Title text);
with data as ( 
select xmlvalue::xml val)
INSERT INTO SAMPLE(Id, Author,Title)
SELECT Id, Author,Title 
FROM   data x, 
XMLTABLE('/Book' 
PASSING val 
COLUMNS  
Id    text  PATH 'Id', 
Author text  PATH 'Author', 
Title text PATH 'Title' )   
; 
return query
select s.Id,s.Author,s.Title from sample s ;
end;
$$
language plpgsql

在尝试执行上述功能时出现以下错误。我从错误中了解到我必须提供 table 别名来引用列。

ERROR:  column reference "id" is ambiguous
LINE 4: SELECT Id, Author,Title 
               ^
DETAIL:  It could refer to either a PL/pgSQL variable or a table column.
QUERY:  with data as ( 
select xmlvalue::xml val)
INSERT INTO SAMPLE(Id, Author,Title)
SELECT Id, Author,Title 
FROM   data x, 
XMLTABLE('/Book' 
PASSING val 
COLUMNS  
Id    text  PATH 'Id', 
Author text  PATH 'Author', 
Title text PATH 'Title' )
CONTEXT:  PL/pgSQL function xml() line 6 at SQL statement
SQL state: 42702

Answer 1

这有效。

create or replace function xml()
returns table(Id text,Author Text,Title Text)
as $$
declare
xmlvalue text := '<Book><Id>1</Id><Author>Subhrendu</Author><Title>Postgre</Title></Book>';
begin
CREATE TEMPORARY TABLE SAMPLE(Id text,Author text,Title text);

with data as ( 
select xmlvalue::xml val)
INSERT INTO SAMPLE(Id, Author,Title)

SELECT d.Id,d.Author,d.Title 
FROM   data x, 
XMLTABLE('/Book' 
PASSING val 
COLUMNS  
Id    text  PATH 'Id', 
Author text  PATH 'Author', 
Title text PATH 'Title' ) as d
; 
return query
select s.Id,s.Author,s.Title from sample s ;
end;
$$
language plpgsql

使用 Xmltable postgres 在 xml 的临时 table 中插入值

Insert values in temporary table from xml using Xmltable postgres

postgresql

plpgsql

xmltable