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Is it a good idea to index datetime field in mysql?
...it in conditions frequently in queries. If your only condition is BETWEEN NOW() AND DATE_ADD(NOW(), INTERVAL 30 DAY) and you have no other index in the condition, MySQL will have to do a full table scan on every query. I'm not sure how many rows are generated in 30 days, but as long as it's less t...
SQL multiple column ordering
...en performs STABLE sorting by column1. This is more clear for people that knows what stable sorting is.
– Atom
Oct 3 '16 at 13:49
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Why do I get a “Null value was assigned to a property of primitive type setter of” error message whe
... relational table (STUDENT) with two columns and ID(int) and NAME(String). Now as ORM you would've made an entity class somewhat like as follows:-
package com.kashyap.default;
import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.G...
What is event bubbling and capturing?
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useCapture now supported in IE >= 9. source
– beatgammit
Aug 20 '13 at 17:10
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How to use gitignore command in git
...nch on github and it pushed all the library and documents into the github. Now what can I do and how can I use gitignore command to avoid the same mistake again.
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How often should you use git-gc?
...hurt to run it more frequently than needed, though.
What I'd do is run it now, then a week from now take a measurement of disk utilization, run it again, and measure disk utilization again. If it drops 5% in size, then run it once a week. If it drops more, then run it more frequently. If it drop...
How does Windows 8 Runtime (WinRT / Windows Store apps / Windows 10 Universal App) compare to Silver
...nd the new Windows 8 Runtime that is used to create Metro style apps. I know you can use it with XAML and it is based on .NET so C# and VB.NET can be used to write the apps, but then it seems to have something to do with HTML, CSS, DOM, and JavaScript.
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Format LocalDateTime with Timezone in Java8
...= DateTimeFormatter.ofPattern("yyyyMMdd HH:mm:ss.SSSSSS Z");
ZonedDateTime.now().format(FORMATTER);
=> "20140829 14:12:22.122000 +09"
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What does iterator->second mean?
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I'm sure you know that a std::vector<X> stores a whole bunch of X objects, right? But if you have a std::map<X, Y>, what it actually stores is a whole bunch of std::pair<const X, Y>s. That's exactly what a map is - it pai...
/etc/apt/sources.list" E212: Can't open file for writing
...udo vim FILE. Or if you don't want to leave your existing vim session (and now have proper sudo rights), you can issue:
:w !sudo tee % > /dev/null
Which will save the file.
HTH
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