MySQL ExtractValue with variable

Question

I have a XML like

 <info>
   <name>John</name>
   <sname>Doe</sname>
 </info>

Table with variables like object_name := "name", object_surname = "sname" And MySQL query like

SELECT @name = CONCAT('/info/', object_name) FROM table

Which give me a variable. @name = '/info/name', it`s OK. Then I do a query:

SELECT ExtractValue(:info, '/info/name') AS name FROM table2

It works fine, but if I change it to

SELECT ExtractValue(:info, @name) AS name FROM table2

It shows nothing. Do you have some solutions?

Sorry, I've misunderstand the question. I hope that you could able to find the correct answer. — SaidbakR
– SaidbakR, Commented Apr 19, 2016 at 13:18
do you set that variable in the same session that you also SELECT? — Sharky
– Sharky, Commented Apr 19, 2016 at 13:18

Mihai · Accepted Answer · 2016-04-19 13:24:27Z

3

SELECT @name = CONCAT('/info/', object_name) FROM table

compares $name to CONCAT....

in your case use

SELECT @name := CONCAT('/info/', object_name) FROM table

answered Apr 19, 2016 at 13:20

Mihai

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