Comments on: Oracle 11g – Virtual Columns – to publish derived column values without storing them. And more… http://technology.amis.nl/blog/2424/oracle-11g-virtual-columns-to-publish-derived-column-values-without-storing-them-and-more Weblog for the AMIS Technology corner Fri, 10 Feb 2012 16:47:37 +0000 http://wordpress.org/?v=2.9 hourly 1 By: Lucas Jellema http://technology.amis.nl/blog/2424/oracle-11g-virtual-columns-to-publish-derived-column-values-without-storing-them-and-more/comment-page-1#comment-263795 Lucas Jellema Thu, 04 Oct 2007 09:36:06 +0000 http://technology.amis.nl/blog/?p=2424#comment-263795 Arnoud, unfortunately the column expression may only refer to columns in the table on which the Virtual Column is defined.<br /> <br /> However, you can use a user defined function in the Virtual Column expression; that function could perform a query from another table! By doing so, you violate the DETERMINISTIC character of the function - on your head be the consequences - and if you do not use the PRAGMA AUTONOMOUS_TRANSACTION you can run into Mutating Table problems, but otherwise it could work that way.<br /> <br /> best regards, Lucas Arnoud, unfortunately the column expression may only refer to columns in the table on which the Virtual Column is defined.

However, you can use a user defined function in the Virtual Column expression; that function could perform a query from another table! By doing so, you violate the DETERMINISTIC character of the function – on your head be the consequences – and if you do not use the PRAGMA AUTONOMOUS_TRANSACTION you can run into Mutating Table problems, but otherwise it could work that way.

best regards, Lucas

]]> By: Arnoud Roth http://technology.amis.nl/blog/2424/oracle-11g-virtual-columns-to-publish-derived-column-values-without-storing-them-and-more/comment-page-1#comment-263793 Arnoud Roth Thu, 04 Oct 2007 09:28:14 +0000 http://technology.amis.nl/blog/?p=2424#comment-263793 This is really great stuff! One question: Is is also possible to define a virtual column to a table based on information stored in another table (e.g. add a virtual column address to emp) Arnoud This is really great stuff!
One question: Is is also possible to define a virtual column to a table based on information stored in another table (e.g. add a virtual column address to emp)
Arnoud

]]>