I am facing an issue while enabling monitoring on indexes , I executed following command to enable index monitoring and then checked the entry in v$object_usage view but couldn’t find any record in it : O/p is Index REPORT.DY_SUM_DLY_SCH_TRN_DIV altered. Checking the entry in v$object_usage : In output …
Tag: indexing
Junction table indexing in many-to-many relationship
Let’s say we have a PRODUCT table, ORDER table and a junction table PRODUCT_ORDER. I create a junction table with the following script: Also an index for the PK was created automatically: It is expected that there will be practically only read operations for these tables and I would like to index the ju…
Why is SQL Server Full Text Search indexing SCR or SUR acronym followed by a number, together?
I discovered a very odd behavior of SQL Server Full Text Search which is indexing SUR, SCR and possibly some other acronyms, together with a number following it – as “Exact Match”. keyword group_id phrase_id occurrence special_term display_term expansion_type source_term s u r 1 2 3 4 5 1 0 …
HANA: How to add a unique contraint on a column that is already indexed?
Having the following schema: I am trying to a unique contraint to the column. But this runs into an error: I can understand that the column is already indexed because I have created the index by myself. But I want the column to be unique. Is there a way to do this? Answer This is indeed an undocumented limita…
sp_BlitzCache and missing index but index columns are already there
I have this recommendation as a missing index on a table for a stored procedure that is ran from the script tool sp_BlitzCache. However I have an index on the columns TeamId, PlayerId, and Active already. Shouldn’t this be used instead and not duplicate indexes with the same columns? The query must be t…
Email address lookup in SQL Server
We have a large subscriber database and have a lookup based on email address of type nvarchar(100). It sometimes times out probably because of a large scan of it. I want to improve this, but weary of some of the options. Would an index on it be ok, I can handle the additional storage if needed, or a computed …
Assuming there is enough disc space, can I create an index in a live production database without risk of downtime?
In a PostgreSQL database, assuming there is enough disc space, can I create an index in a live production database without risk of downtime? In other words, are there locks or possible crash or data loss possible or something else with the creation of an index. To be more precise, it’s an index on a JSO…
Should the column used to order results be included in the index of a postgresql table?
I am creating indexes for a PostgreSQL database. I would like to know whether the column(s) used to order results in a PostgreSQL statement should be included in the index. Assume I have created a …
What could be the possible drawbacks of using force index clause in mysql query? [closed]
Closed. This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 1 year ago. Improve this question Sample Example – SELECT * FROM table_name FORCE INDEX (index_list) WH…
What is an on-disk structure?
An index is an on-disk structure. I couldn’t find anything understandable. For example, I found this Is it like a file system? Answer It just means that the index is physically stored on disk, as opposed to “only exists in-memory”. Your link is not related at all.