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MIN/MAX vs ORDER BY and LIMIT

...oks like MIN() is able to simply pluck the smallest value from the index ('Select tables optimized away' and 'NULL' rows) whereas the SORT and LIMIT still needs needs to do an ordered traversal of the index (106,000 rows). The actual performance impact is probably negligible. It looks like MIN() i...
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When to use enumerateObjectsUsingBlock vs. for

... support to implement enumeration). Fast enumeration requires translation from an internal representation to the representation for fast enumeration. There is overhead therein. Block-based enumeration allows the collection class to enumerate contents as quickly as the fastest traversal of the nat...
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IndexOf function in T-SQL

... CHARINDEX is what you are looking for select CHARINDEX('@', 'someone@somewhere.com') ----------- 8 (1 row(s) affected) -or- select CHARINDEX('c', 'abcde') ----------- 3 (1 row(s) affected) ...
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Binding ng-model inside ng-repeat loop in AngularJS

... what about the e2e test of this code? I mean how to select an input if it model is dynamic? – devmao Jul 1 '13 at 9:00 1 ...
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On logout, clear Activity history stack, preventing “back” button from opening logged-in-only Activi

...n my application require a user to be logged-in to view. Users can log out from almost any activity. This is a requirement of the application. At any point if the user logs-out, I want to send the user to the Login Activity . At this point I want this activity to be at the bottom of the history sta...
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Adding an identity to an existing column

... ) ON [PRIMARY] go SET IDENTITY_INSERT dbo.Tmp_Names ON go IF EXISTS ( SELECT * FROM dbo.Names ) INSERT INTO dbo.Tmp_Names ( Id, Name ) SELECT Id, Name FROM dbo.Names TABLOCKX go SET IDENTITY_INSERT dbo.Tmp_Names OFF go DROP...
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How to create a jQuery plugin with methods?

... this technique! It doesn't create a new instance for every element in the selector like you think you're doing, instead it creates only a single instance attached to the selector itself. View my answer for a solution. – Kevin Jurkowski Apr 10 '14 at 1:14 ...
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How do I do string replace in JavaScript to convert ‘9.61’ to ‘9:61’?

... $("#text").val(); // value = 9.61 use $("#text").text() if you are not on select box... value = value.replace(".", ":"); // value = 9:61 // can then use it as $("#anothertext").val(value); Updated to reflect to current version of jQuery. And also there are a lot of answers here that would best ...
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How random is JavaScript's Math.random?

... 90 have 2 digits 900 have 3 digits 1 has 4 digits and so on. So if you select some at random, then that vast majority of selected numbers will have the same number of digits, because the vast majority of possible values have the same number of digits. ...
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MySql export schema without data

...e the view definition. So if yo had a view like following create view v1 select `a`.`id` AS `id`, `a`.`created_date` AS `created_date` from t1; with --no-data option, view definition will get changed to following create view v1 select 1 AS `id`, 1 AS `created_date` ...