[SQL] select xpath ...

[boris]

hi all,
I've inserted xml file :


xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";>


zz
..


to a table:

CREATE TABLE "temp".tempxml
(
  record xml
)

I can get it using:
select * from temp.tempxml


but, I can't get any values using xpath. ex:


  select (xpath('/document/title/text()', record ))[1] from temp.tempxml


am I doing it right?

thanks.




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Re: [SQL] Window function sort order help

[nicoletta maia]

2011/9/13 Dianna Harter :

Hi,

> [snip]
> Any suggestions to get the order by to occur first then the partition by or
> maybe there another approach that I could use?

I tried to write the query without using the window:

SELECT  `X`.`consumer_id`, `X`.`move_date` ,  `X`.`history_timestamp` ,
 MIN(  `Y`.`history_timestamp` ) AS `start_time`
FROM
`Table` AS `X`
JOIN
`Table` AS `Y`
ON  `X`.`consumer_id` = `Y`.`consumer_id`
AND `X`.`move_date` =  `Y`.`move_date`
AND  `X`.`history_timestamp` >=  `Y`.`history_timestamp`
LEFT JOIN
`Table` AS `Z`
ON  `X`.`consumer_id` = `Z`.`consumer_id`
AND `X`.`move_date` <>  `Z`.`move_date`
AND  `X`.`history_timestamp` >=  `Z`.`history_timestamp`
AND  `Y`.`history_timestamp` <=  `Z`.`history_timestamp`
WHERE  `Z`.`consumer_id` IS NULL
GROUP BY   `X`.`consumer_id`, `X`.`move_date` ,  `X`.`history_timestamp`
ORDER BY  `X`.`consumer_id`, `X`.`history_timestamp` ASC

To avoid the LEFT JOIN, you can move the control in the sub-query:

SELECT  `X`.`consumer_id`, `X`.`move_date` ,  `X`.`history_timestamp` ,
MIN(  `Y`.`history_timestamp` ) AS `start_time`
FROM
`Table` AS `X`
JOIN
`Table` AS `Y`
ON  `X`.`consumer_id` = `Y`.`consumer_id`
AND `X`.`move_date` =  `Y`.`move_date`
AND  `X`.`history_timestamp` >=  `Y`.`history_timestamp`
WHERE  NOT EXISTS (
SELECT *
FROM `Table` AS `Z`
WHERE `X`.`consumer_id` = `Z`.`consumer_id`
AND `X`.`move_date` <>  `Z`.`move_date`
AND  `X`.`history_timestamp` >=  `Z`.`history_timestamp`
AND  `Y`.`history_timestamp` <=  `Z`.`history_timestamp`
)
GROUP BY   `X`.`consumer_id`, `X`.`move_date` ,  `X`.`history_timestamp`
ORDER BY  `X`.`consumer_id`, `X`.`history_timestamp` ASC

With Y I select history_timestamp preceding the current row with the
same move_date.
With Z I verify that no changes have occurred to move_date between
X.history_timestamp and Y.history_timestamp.

Ciao!

Nicoletta

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