Stack Overflow
Stack Overflow

Questions tagged [non-clustered-index]

Non-Clustered Index contains pointers to the data that is stored in the data page. In Non-Clustered Index logical order doesn’t match with physical order of stored data on disk.

Non-Clustered Index contains pointers to the data that is stored in the data page. In Non-Clustered Index logical order doesn’t match with physical order of stored data on disk. Non-clustered index contains index key to the table records in the leaf level. There can be one or more Non-clustered indexes in a table.

234 questions
0
votes
1 answer

Clustered index vs composite index. Which one is better?

I am using Microsoft SQL Server 2017. I have table called ProductMapping. Below is the table structure: CREATE TABLE [dbo].[Accommodation_ProductMapping]( [ProductMappingId] [uniqueidentifier] NOT NULL, [AccommodationId] [uniqueidentifier]…
user2043071
  • 105
  • 1
  • 2
  • 15
0
votes
0 answers

SQL Server - free disk space after dropping index

After creating a nonclustered index on a SQL Server table, it leads to disk space used increase. Even after we dropped the index, the difference of disk space in use used didn't change. Before creating the nonclustered index, total size on disk was…
Abba
  • 519
  • 6
  • 17
0
votes
1 answer

Lost NCIndex (NDF) file to one of my DBs. Can anything be done with just the MDF? Any reads possible at all?

Lost NCIndex (NDF) file to one of my DBs. Can anything be done with just the MDF? Any reads possible at all? I assume not, but figured I'd ask anyways.
Matt
  • 25,943
  • 66
  • 198
  • 303
0
votes
1 answer

Any possible way to avoid order by desc to select top 500 latest records. Since sorting causes so many performance issue,

I have a table with two columns c1 and c2 both are integer. I have to select top 500 latest records with out order by desc. Table has more than 50 million records. c1 is clustered index with "order by asc". Cannot remove the clustered index done…
manu vijay
  • 367
  • 3
  • 13
0
votes
2 answers

execution plan suggesting to add an index on columns which are not part of where clause

I am running following query in SSMS and execution plan suggesting to add index on columns which are not part of where clause. I was planning to add index on two columns which are being used in where clause (OID and TransactionDate). SELECT …
user1263981
  • 2,953
  • 8
  • 57
  • 98
0
votes
1 answer

Why does creating non-clustered index slow down data retrieval?

My understanding was that indexing improve data retrieval speed. Bit confused on this occasion and want to seek some advise. I have a table with millions of records. It takes around 90 seconds to fetch data using the select query and the where…
variable
  • 8,262
  • 9
  • 95
  • 215
0
votes
0 answers

SQL Server Index Worked (Too Well, Near Enough Instantly!)

I have a table with 2.5 million rows (I know, development nearly finished to warehouse this). The system querying has been suffering some SQL timeouts understandably. I profiled a few of my queries and noticed 97% of the work was scanning an…
user10058046
0
votes
1 answer

Azure Data Sync: Failed to perform data sync operation: Table do not have clustered index

I'm getting the 1: https://i.stack.imgur.com/EiSRL.png I realize there is an earlier post about this topic with an answer that seems to have been suitable for at least 2 people so far. Azure Data Sync Clustered Index Error However, I have tried…
Wuf_fang
  • 21
  • 4
0
votes
2 answers

How to use non-clustered index?

I have general question about non-clustered index working suppose I have 4 non clustered index on my table and I want to know that which non-clustered index is calling form these 4 indexes and is there ant way to use a specific index from these 4…
Muhammad Usman Rasheed
  • 13
  • 4
0
votes
1 answer

How does sql server look up in composite non-clustered index?

If for example I have composite non-clustered index as following: CREATE NONCLUSTERED INDEX idx_Test ON dbo.Persons(IsActive, UserName) Depending on this answer How important is the order of columns in indexes? If I run this query : Select * From…
Simple Code
  • 2,354
  • 2
  • 27
  • 56
0
votes
1 answer

Azure Data Sync Clustered Index Error

We are trying to setup an Azure Database Sync group to replicate our data from an on-premise server to an Azure SQL database. This as a first step for a migration to Azure. The Sync Group and Sync Agent have all been set up. When we press the…
Fluffymittens
  • 170
  • 7
0
votes
1 answer

How to Create Multi-level Index in MySql and how to find out a column is Multi-level indexed?

I have a table 'activities'. it consists of around 1 million records. its columns consists off, id(PK), u_id(FK), cl_id(FK), activity_log By Default id(PK) is indexed and i have created my own index for u_id and cl_id by using, ALTER TABLE…
Crysis
  • 418
  • 2
  • 7
  • 28
0
votes
1 answer

Questions about indexing in SQL with Clustered and Non-clustered

If i have table with two column: id and priority. Id is primary key priority is number, unique and have indexing (Non-clustered). So if i search by id or by priority. Which one is faster and why?
Le Dinh Dam
  • 112
  • 7
0
votes
1 answer

Subquery in the WHERE clause in Nonclustered Filtered Index

I'm using SSMS 2016 and trying to create a Filtered nonclustered index on the two columns which are used in the JOIN and Where Conditions. Is it allowed to use Subquery in the WHERE Clause when filtering index. Below is corresponding example:…
Data Engineer
  • 795
  • 16
  • 41
0
votes
2 answers

SQL Server Non Clustered Index - Include values

I'm relatively new to the world of SQL Server Optimization and Indexes. I ran a query that recommends missing indexes (https://blog.sqlauthority.com/2011/01/03/sql-server-2008-missing-index-script-download/) and I'm having trouble understanding the…
Carl Grzywacz MSFT
  • 23
  • 6
1 2 3
…
15 16