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What do Clustered and Non clustered index actually mean?
...h a clustered index the rows are stored physically on the disk in the same order as the index. Therefore, there can be only one clustered index.
With a non clustered index there is a second list that has pointers to the physical rows. You can have many non clustered indices, although each new index...
Is the order of elements in a JSON list preserved?
I've noticed the order of elements in a JSON object not being the original order.
5 Answers
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List vs Set vs Bag in NHibernate
...
NHibernate semantics:
List: Ordered collection of entities, duplicate allowed. Use a .NET IList in code. The index column will need to be mapped in NHibernate.
Set: Unordered collection of unique entities, duplicates not allowed. Use Iesi.Collection.ISe...
How to get next/previous record in MySQL?
...o cemkalyoncu's solution:
next record:
SELECT * FROM foo WHERE id > 4 ORDER BY id LIMIT 1;
previous record:
SELECT * FROM foo WHERE id < 4 ORDER BY id DESC LIMIT 1;
edit: Since this answer has been getting a few upvotes lately, I really want to stress the comment I made earlier about un...
How to delete the top 1000 rows from a table using Sql Server 2008?
...ct two statements. A DELETE followed by a SELECT.
You don't define TOP as ordered by what.
For a specific ordering criteria deleting from a CTE or similar table expression is the most efficient way.
;WITH CTE AS
(
SELECT TOP 1000 *
FROM [mytab]
ORDER BY a1
)
DELETE FROM CTE
...
Drop all the tables, stored procedures, triggers, constraints and all the dependencies in one sql st
...= (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'P' AND category = 0 ORDER BY [name])
WHILE @name is not null
BEGIN
SELECT @SQL = 'DROP PROCEDURE [dbo].[' + RTRIM(@name) +']'
EXEC (@SQL)
PRINT 'Dropped Procedure: ' + @name
SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WH...
Order Bars in ggplot2 bar graph
...
The key with ordering is to set the levels of the factor in the order you want. An ordered factor is not required; the extra information in an ordered factor isn't necessary and if these data are being used in any statistical model, the w...
MySQL select 10 random rows from 600K rows fast
... to gaps, to non-uniform with gaps.
http://jan.kneschke.de/projects/mysql/order-by-rand/
For most general case, here is how you do it:
SELECT name
FROM random AS r1 JOIN
(SELECT CEIL(RAND() *
(SELECT MAX(id)
FROM random)) AS id)
AS r2
...
Delete all data in SQL Server database
...ea off. Here she clarifies "you have to drop the referencing constraint in order to truncate the table."
– Martin Smith
Oct 2 '10 at 0:38
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Linq select objects in list where exists IN (A,B,C)
I have a list of orders .
I want to select orders based on a set of order statuses.
5 Answers
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