Solved

Oracle Text Contains Problem

Posted on 2009-06-30
3
568 Views
Last Modified: 2013-12-19
Hi Everyone,
I'm using the Oracle Text contains function, but it sometimes doesn't work properly.  It returns 0 (text not found) when the text is actually there.

For example:

select e.* , contains(e.emp_name, '%Jones%') as cont_val
from emp_table e
where e.emp_name = 'Jones'

Returns a row with cont_val = 0 (which means text not found).  Results for %Jones% in the contains function in the where clause return no rows.  This is a sporadic problem that only occurs for some rows in our table.  We're using Oracle 10.2.0.1.0.
Any ideas what's going on?
Thanks

0
Comment
Question by:leclaude
  • 2
3 Comments
 
LVL 40

Expert Comment

by:mrjoltcola
ID: 24828838
How are you updating your text indexes? They are not immediately synched and must be maintained, unlike regular indexes.

http://download.oracle.com/docs/cd/B15595_01/content.101/b14493/text.htm#sthref776

See the docs on ctx_ddl.sync_index() for manually synching, try a manual sync and see if it shows.

0
 
LVL 1

Author Comment

by:leclaude
ID: 24903920
Why would an index need to be synched to return a row? At worst the query should be slow, but not miss results.
0
 
LVL 40

Accepted Solution

by:
mrjoltcola earned 500 total points
ID: 24906622
That is how text indexes work. Text indexes are not standard Oracle b-tree indexes. The update does not happen immediately upon insert or update of the rows. Instead the change is scheduled, and will be applied when the next sync is run. In 10g and 11g I believe there is a setting that forces immediate update but it is poor for performance.

Please read this for an explanation:

http://www.oracle.com/technology/products/text/htdocs/Index_Maintenance.html
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Truncate is a DDL Command where as Delete is a DML Command. Both will delete data from table, but what is the difference between these below statements truncate table <table_name> ?? delete from <table_name> ?? The first command cannot be …
Cursors in Oracle: A cursor is used to process individual rows returned by database system for a query. In oracle every SQL statement executed by the oracle server has a private area. This area contains information about the SQL statement and the…
This video shows, step by step, how to configure Oracle Heterogeneous Services via the Generic Gateway Agent in order to make a connection from an Oracle session and access a remote SQL Server database table.
This video shows syntax for various backup options while discussing how the different basic backup types work.  It explains how to take full backups, incremental level 0 backups, incremental level 1 backups in both differential and cumulative mode a…

863 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

22 Experts available now in Live!

Get 1:1 Help Now