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SQL Server indexes - ascending or descending, what difference does it make?
...TE INDEX ix_index ON mytable (col1, col2 DESC);
can be used for either:
SELECT *
FROM mytable
ORDER BY
col1, col2 DESC
or:
SELECT *
FROM mytable
ORDER BY
col1 DESC, col2
, but not for:
SELECT *
FROM mytable
ORDER BY
col1, col2
An index on a single colum...
How to find all duplicate from a List? [duplicate]
...d then filter out any of the enumerables that have a Count of <=1, then select their keys to get back down to a single enumerable:
var duplicateKeys = list.GroupBy(x => x)
.Where(group => group.Count() > 1)
.Select(group => group.Key);
...
Finding duplicate values in MySQL
...
Do a SELECT with a GROUP BY clause. Let's say name is the column you want to find duplicates in:
SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;
This will return a result with the name value in the first colum...
Importing a Maven project into Eclipse from Git
...t. M2Eclipse will help you along by prompting you on the Import menu.
Select the "Import..." context menu from the Package Explorer view
Select "Check out Maven projects from SCM" option under the Maven category
On the window that is presented choose the link "Find more SCM connectors in the m2...
MySQL select where column is not empty
In MySQL, can I select columns only where something exists?
13 Answers
13
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Eclipse: How do i refresh an entire workspace? F5 doesn't do it
...le->Refresh , it doesn't really refresh anything (perhaps the currently selected project). How do I get eclipse to refresh all of the projects?
...
Can I have multiple Xcode versions installed?
... explicitly specify it at install time. Also, you will generally want to unselect all features besides the xcode core tools, because the others don't let you change the install directory.
– Paul Du Bois
Jul 3 '11 at 3:30
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Select all 'tr' except the first one
How can I select all tr elements except the first tr in a table with CSS?
10 Answers
...
Why does the jquery change event not trigger when I set the value of a select using val()?
... not being run when the value is set by val() , but it does run when user selects a value with their mouse. Why is this?
9...
MySQL Select Query - Get only first 10 characters of a value
...
Using the below line
SELECT LEFT(subject , 10) FROM tbl
MySQL Doc.
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