How to get N rows from a table in Sql Server database? it is difficult to get random Ids of the tables by using any logic, we will need to loop to create N ids but the technique we will explore here will not need any looping or any Id creation in temporary table but the very simple ways to achieve our goal
So let's take the very first one
We have function in Sql Server "NEWID()", do you know what it return, let's check it
Select top 10 NEWID() from products
I used to get the 10 rows otherwise we will need to loop, here is the output:
A582542D-44AE-43D4-B34A-0BDFFC9E99B8
B1C4DA4A-1C12-4D2E-B714-255AB3A81B35
40C66BCB-F775-4886-BD20-85B30914C030
FDF74E8D-4234-4C42-887D-DFB18E5D2F4C
A6AEEA9C-5A38-4BBF-9196-D889FC9A780D
8EC5B2AA-28A1-4A64-9FB4-E3BC9E1F340C
6D156522-C3A7-450E-AAB0-36CFC9446E3B
BD5848FB-6D3E-4546-976A-973A04FF726F
E0A6D374-41EC-4A4F-BA88-2C6B26887CEB
843A7209-8348-4E06-92AE-AD1C7BE33EC4
If we can order our records by using this new id will solve our problem, so why we are waiting, let's try to get 10 products Ids by using this logic
Select top (10) [ProductId]
From [Products]
order by NewId()
ProductId
143
108
47
26
121
53
71
205
196
34
So if we can use the above query as sub-query our goal is achieved
Select *
From Products
Where ProductId IN
(Select top (@Rows) [ProductId] from [Products]
where CategoryId = @CategoryId
order by NewId())
Every time it will give 10 random product list, if you can notice we user where clause to get the records of a particular category only.
Enjoy it
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Having 13+ years of experience in Microsoft Technologies (C#, ASP.Net, MVC and SQL Server). Worked with Metaoption LLC, for more than 9 years and still with the same company. Always ready to learn new technologies and tricks.
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| By Ali Adravi On 03 May, 14 Viewed: 910 |
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