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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.

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What do Clustered and Non-Clustered index actually mean?

I have a limited exposure to DB and have only used DB as an application programmer. I want to know about Clustered and Non clustered indexes. I googled and what I found was : A clustered index is a special type of index that reorders the way …
P.K
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What are the differences between a clustered and a non-clustered index?

What are the differences between a clustered and a non-clustered index?
Eric Labashosky
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Difference between clustered and nonclustered index

I need to add proper index to my tables and need some help. I'm confused and need to clarify a few points: Should I use index for non-int columns? Why/why not I've read a lot about clustered and non-clustered index yet I still can't decide when to…
Pabuc
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SQL Server - When to use Clustered vs non-Clustered Index?

I know primary differences between clustered and non clustered indexes and have an understanding of how they actually work. I understand how clustered and non-clustered indexes improve read performance. But one thing I am not sure is that what would…
armulator
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How do I check if a nonclustered index exists in SQL Server 2005

I have the following: CREATE NONCLUSTERED INDEX [MyTableIndex] ON [dbo].[tablename] ([tablename_ID],[tablename_Field1]) INCLUDE ([Tablename_Field2],[Tablename_Field3]) I want to create an if statement to check if this exists. How do I do this?
user532104
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Why can't I simply add an index that includes all columns?

I have a table in SQL Server database which I want to be able to search and retrieve data from as fast as possible. I don't care about how long time it takes to insert into the table, I am only interested in the speed at which I can get data. The…
Niels Brinch
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How to drop a unique constraint from table column?

I have a table 'users' with 'login' column defined as: [login] VARCHAR(50) UNIQUE NOT NULL Now I want to remove this unique constraint/index using SQL script. I found its name UQ_users_7D78A4E7 in my local database but I suppose it has a different…
SKINDER
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Does the order of columns in an multicolumn non-clustered index matter in SQL Server?

Does the order of columns in a multi-column nonclustered index created for a SQL Server table really matter? E.g. Is CREATE NONCLUSTERED INDEX [MultiFieldIndex_1] ON [Table_01] ([Column_A],[Column_B],[Column_C],[Column_D]) same as CREATE…
Priyal
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Does sqlite support indexes?

can anyone tell me if Sqlite supports clustered and nonclustered indexes? and if it does how do i make a column which is non primary key a nonclustered index? I am very new to database concepts hence very confused..
alitha
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primary key is always indexed in sql server?

You can create a clustered index on a column other than primary key column if a nonclustered primary key constraint was specified. http://msdn.microsoft.com/en-us/library/ms186342.aspx So the above told me: I can create a clustered index on…
ZZZ
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Difference between Cluster and Non-cluster index in SQL

Just for knowledge in interview question, and my knowledge. SQL - Difference between Cluster and Non-cluster index?
AjmeraInfo
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SQL Server creating multiple nonclustered indexes for one column vs having multiple columns in just one index

Suppose I have following table UserID (Identity) PK UserName - unique non null UserEmail - unique non null What is recommended for the best performance? creating non clustered index for UserName and UserEmail separately OR Just one including…
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Row Locator in Non Clustered Index

I was reading about Non Clustered Index which says that "Nonclustered index contain only the values from the indexed columns and row locators that point to the actual data rows, rather than contain the data rows themselves. This means that the query…
Nilish
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Why does SQL Server use a non-clustered index over the clustered PK in a "select *" operation?

I've got a very simple table which stores Titles for people ("Mr", "Mrs", etc). Here's a brief version of what I'm doing (using a temporary table in this example, but the results are the same): create table #titles ( t_id tinyint not null…
gerrod
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Does INDEX() create a clustered or non-clustered index in MySQL?

I am learning from a tutorial that uses INDEX() within a CREATE TABLE statement, but does not explain whether it is clustered or non-clustered. My question is: does INDEX() when used in a CREATE TABLE statement result in a clustered or non-clustered…
developer098
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