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INNER JOIN vs LEFT JOIN performance in SQL Server
... version is able to replace one of the clustered index scans with a seek - meaning that this will literally be an order of magnitude faster with a large number of rows.
So the conclusion is more or less what I mentioned several paragraphs above; this is almost certainly an indexing or index coverag...
How does database indexing work? [closed]
...,778 block accesses required by the non-indexed table." doesn't the author mean 1,000,000 block accesses? 277,778 is the number of blocks required by the index itself. There seems to be a couple of other inaccuracies too :(
– jcm
Aug 24 '14 at 4:02
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Custom method names in ASP.NET Web API
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By default the route configuration follows RESTFul conventions meaning that it will accept only the Get, Post, Put and Delete action names (look at the route in global.asax => by default it doesn't allow you to specify any action name => it uses the HTTP verb to dispatch). So when ...
How to name factory like methods?
...ng else? Is it only a matter of taste? A convention? Or is there a special meaning in "create"?
11 Answers
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MySQL Data - Best way to implement paging?
...records or get a repeated record. This is because adding or removing a row means that the offset of all the rows after it changes. In your case it's probably not important - I guess your pool of adverts doesn't change too often and anyway no-one would notice if they get the same ad twice in a row - ...
Difference between one-to-many and many-to-one relationship
...but from different perspectives. In the same way that "A is a subset of B" means the same as "B is a superset of A".
– nvogel
Jun 25 '16 at 10:12
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MySQL - Using COUNT(*) in the WHERE clause
...count() with where. now see why ....
where is not same as having , having means you are working or dealing with group and same work of count , it is also dealing with the whole group ,
now how count it is working as whole group
create a table and enter some id's and then use:
select count(*) f...
Generate a random number in the range 1 - 10
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If by numbers between 1 and 10 you mean any float that is >= 1 and < 10, then it's easy:
select random() * 9 + 1
This can be easily tested with:
# select min(i), max(i) from (
select random() * 9 + 1 as i from generate_series(1,1000000)
) q;
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Checkbox for nullable boolean
... and the third button represents your null, whatever the semantics of null means. You could use a <select><option> drop down list to save real estate, but the user has to click twice and the choices aren't nearly as instantaneously clear.
1 0 null
True False Not Set
Yes ...
How to remove the border highlight on an input text element
...n of the focus event, not the actual event. Removing the visual indication means you're making it harder for people with disabilities who rely on that indication.
– Boaz
Jan 31 '13 at 9:48
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