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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...NULL into a column with a NOT NULL constraint.
Inserting a row to a partitioned table, but the values you insert don't map to a partition.
If you use REPLACE, MySQL actually does a DELETE followed by an INSERT internally, which has some unexpected side effects:
A new auto-increment ID is alloc...
Unstaged changes left after git reset --hard
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This works, but I do not exactly understand why. Anyone care to explain each command?
– Edwin Stoteler
Mar 20 '15 at 14:04
19
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How do I install pip on macOS or OS X?
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⚡️ TL;DR — One line solution.
All you have to do is:
sudo easy_install pip
2019: ⚠️easy_install has been deprecated. Check Method #2 below for preferred installation!
I made a gif, coz. why not?
Details:
⚡️ OK, ...
Must JDBC Resultsets and Statements be closed separately although the Connection is closed afterward
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What you have done is perfect and very good practice.
The reason I say its good practice... For example, if for some reason you are using a "primitive" type of database pooling and you call connection.close(), the connection will be return...
Unable to import a module that is definitely installed
.../python2.6/site-packages/
Save the file, restart the Terminal, and you're done
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How can I Remove .DS_Store files from a Git repository?
...it-rm once for every .DS_Store file, while xargs will put all the paths on one command line. Mostly I prefer xargs because I don't have to worry about escaping a lot of special characters.
– benzado
Sep 21 '08 at 7:13
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Should methods in a Java interface be declared with or without a public access modifier?
...ecially for each interface. The following example could easily confuse someone, who is not 100% fluent in Java:
public interface Foo{
public void MakeFoo();
void PerformBar();
}
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How to remove item from list in C#?
...r filtered = result.Where(f => f.ID != 2); returns all items except the one with ID 2
Detailed answer:
I think .RemoveAll() is very flexible, because you can have a list of item IDs which you want to remove - please regard the following example.
If you have:
class myClass {
public int ID; pub...
Disable ONLY_FULL_GROUP_BY
... This solution work fine on mySQL 5.7.11 and should be the accepted one. The accepted answer doesn't work on new version of mySQL
– Anyone_ph
Apr 14 '16 at 6:54
5
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Good reasons to prohibit inheritance in Java?
...o be extended, and with enough documentation to describe how it should be done
Classes marked final
If you are writing purely internal code this may be a bit of overkill. However the extra effort involved in adding five characters to a class file is very small. If you are writing only for internal...