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Why is using the rails default_scope often recommend against?

...ate) posts. So far so good. 2.1.1 :001 > Post.all Post Load (0.2ms) SELECT "posts".* FROM "posts" WHERE "posts"."published" = 't' Well this is pretty much what we expect. Now lets try: 2.1.1 :004 > Post.new => #<Post id: nil, title: nil, published: true, created_at: nil, update...
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performSelector may cause a leak because its selector is unknown

...ult of the method you're calling. The result could be anything: void, int, char, NSString *, id, etc. ARC normally gets this information from the header of the object type you're working with.3 There are really only 4 things that ARC would consider for the return value:4 Ignore non-object types (...
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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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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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Should I use the datetime or timestamp data type in MySQL?

...o with the native format. You can do calculations within MySQL that way ("SELECT DATE_ADD(my_datetime, INTERVAL 1 DAY)") and it is simple to change the format of the value to a UNIX timestamp ("SELECT UNIX_TIMESTAMP(my_datetime)") when you query the record if you want to operate on it with PHP. ...
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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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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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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 | +...