[MDEV-7336] ExtractValue function not usable for Virtual Columns Created: 2014-12-16 Updated: 2017-01-12 Resolved: 2017-01-12 |
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| Status: | Closed |
| Project: | MariaDB Server |
| Component/s: | Virtual Columns, XML Functions |
| Affects Version/s: | 10.0.15, 10.0, 10.1 |
| Fix Version/s: | 10.2.1 |
| Type: | Bug | Priority: | Minor |
| Reporter: | Tom Noonan II | Assignee: | Michael Widenius |
| Resolution: | Fixed | Votes: | 0 |
| Labels: | None | ||
| Environment: |
Linux - CentOS6 |
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| Description |
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When creating a table I am unable to use the ExctractValue function to create a column, despite it being deterministic: mysql> create table xml_test (xml TEXT, virt CHAR(16) AS (ExtractValue(xml, '//some/@xpath')) PERSISTENT; This was discussed several years ago on the dev list at https://www.mail-archive.com/maria-developers@lists.launchpad.net/msg03488.html where it was added to Launchpad bug 608641 (https://bugs.launchpad.net/maria/+bug/608641). Bug 608641 contains other functions as well and was quietly closed as "won't fix" in 2012 with no explanation. I have a use where being able to create and index columns off stored XML would be very useful. I need to use xpath searches, I cannot use simple string manipulation. I would appreciate if this could be reevaluated. If it is still "won't-fix" please document why. Thank you. |
| Comments |
| Comment by Elena Stepanova [ 2014-12-18 ] |
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igor, Could you please elaborate on the 'Won't fix' decision which was made in https://bugs.launchpad.net/maria/+bug/608641, and somehow summarize the limitations at https://mariadb.com/kb/en/mariadb/documentation/sql-commands/data-definition/create/virtual-columns/ ? |
| Comment by Sergei Golubchik [ 2017-01-12 ] |
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Since 10.2.1 ExctractValue can be used in generated columns, virtual and persistent. |