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LINQ with groupby and count

...(var line in data.GroupBy(info => info.metric) .Select(group => new { Metric = group.Key, Count = group.Count() }) .OrderBy(x => x.Metric)) { Console.Wri...
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Sequence contains no elements?

...in dc.BlogPosts where p.BlogPostID == id select p).Single(); Also; if this is LINQ-to-SQL, then in the current version you get a slightly better behaviour if you use the form: var id = ID; BlogPost post = dc.BlogPosts.Single(p => p.BlogPostID == id); ...
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Parallel.ForEach() vs. foreach(IEnumerable.AsParallel())

...the AsParallel() call, like: var fibonacciNumbers = numbers.AsParallel().Select(n => ComputeFibonacci(n)); share | improve this answer | follow | ...
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Can I use multiple “with”?

... Try: With DependencedIncidents AS ( SELECT INC.[RecTime],INC.[SQL] AS [str] FROM ( SELECT A.[RecTime] As [RecTime],X.[SQL] As [SQL] FROM [EventView] AS A CROSS JOIN [Incident] AS X WHERE patindex('%' + A.[Col] + ...
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When should I use a table variable vs temporary table in sql server?

... source for the data inserted to the table is from a potentially expensive SELECT statement then consider that using a table variable will block the possibility of this using a parallel plan. If you need the data in the table to survive a rollback of an outer user transaction then use a table variab...
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Delete all records in a table of MYSQL in phpMyAdmin

...ampserver 2.2. When I want to delete all records of a table in phpMyAdmin (select all) it deletes only one record not all records. Why it does not delete all records? ...
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How to apply two CSS classes to a single element

...To target elements that contain all of the specified classes, use this CSS selector (no space) (ref): .c1.c2 { } share | improve this answer | follow | ...
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Best way to check if object exists in Entity Framework?

... hi. how can we check if it exists and after that select all its data? – virtouso Apr 7 '15 at 1:27 1 ...
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String concatenation in MySQL

...most DBMSs use of + or || for concatenation. It uses the CONCAT function: SELECT CONCAT(first_name, " ", last_name) AS Name FROM test.student As @eggyal pointed out in comments, you can enable string concatenation with the || operator in MySQL by setting the PIPES_AS_CONCAT SQL mode. ...
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Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?

...pdated) values(null, null); Query OK, 1 row affected (0.06 sec) mysql> select * from t5; +----+---------------------+---------------------+ | id | stamp_created | stamp_updated | +----+---------------------+---------------------+ | 2 | 2009-04-30 09:44:35 | 2009-04-30 09:44:35 | +...