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Randomize a List
...uffle();
The code above uses the much criticised System.Random method to select swap candidates. It's fast but not as random as it should be. If you need a better quality of randomness in your shuffles use the random number generator in System.Security.Cryptography like so:
using System.Security....
Returning IEnumerable vs. IQueryable
...mers = custs.Where(c => c.IsGold);
That code will execute SQL to only select gold customers. The following code, on the other hand, will execute the original query in the database, then filtering out the non-gold customers in the memory:
IEnumerable<Customer> custs = ...;
// Later on...
...
Open new Terminal Tab from command line (Mac OS X)
...masReggi: Add -e 'tell application "Terminal" to do script "echo hello" in selected tab of the front window' to the end of the osascript command.
– Gordon Davisson
Aug 26 '12 at 20:14
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How to generate a new Guid in stored procedure?
... using SQL Server. I'm sure other database system have similar functions.
select NEWID()
If you're using Oracle then you can use the SYS_GUID() function. Check out the answer to this question: Generate a GUID in Oracle
sh...
invalid target release: 1.7
...ct JDK in your Maven run configuration. Go to Run -> Run Configuration, select your Maven Build configuration, go to JRE tab and set the correct Runtime JRE.
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Razor comment syntax
...
In visual studio, select some code/markup in your razor view and press Ctrl+K, Ctrl+C, and it'll comment the selection as described above.
– MrBoJangles
Feb 17 '11 at 18:12
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INNER JOIN vs LEFT JOIN performance in SQL Server
...(ID, Name) VALUES (4, 'Four')
INSERT #Test2 (ID, Name) VALUES (5, 'Five')
SELECT *
FROM #Test1 t1
INNER JOIN #Test2 t2
ON t2.Name = t1.Name
SELECT *
FROM #Test1 t1
LEFT JOIN #Test2 t2
ON t2.Name = t1.Name
DROP TABLE #Test1
DROP TABLE #Test2
If you run this and view the execution plan, you'll se...
Cast from VARCHAR to INT - MySQL
...NED [INTEGER]
TIME
UNSIGNED [INTEGER]
Therefore, you should use:
SELECT CAST(PROD_CODE AS UNSIGNED) FROM PRODUCT
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Hide files with certain extension in Sublime Text Editor?
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Are you talking about the sidebar? For example, if you select File → Open and select a folder, then the folder and its contents are displayed along the left side, allowing you to navigate amongst its contents and sub-directories. If that is the case, then the answer is yes, fi...
How to deal with SettingWithCopyWarning in Pandas?
...owing, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] =...