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INSERT … ON DUPLICATE KEY (do nothing)
... uses resources for the second action.
Use INSERT IGNORE ...,
Negative : MySQL will not show any errors if something goes wrong, so you cannot handle the errors. Use it only if you don’t care about the query.
share
...
“use database_name” command in PostgreSQL
...
If I'm not mistaken, databases in MySQL are more akin to schemas in PostgreSQL -- you can switch between those, but DBs in PostgreSQL are a whole different ballgame.
– mpen
May 10 '12 at 3:40
...
Improve INSERT-per-second performance of SQLite
...com/rdpoor/CreateOrUpdate
which bulk loads an array of ActiveRecords into MySQL, SQLite or PostgreSQL databases. It includes an option to ignore existing records, overwrite them or raise an error. My rudimentary benchmarks show a 10x speed improvement compared to sequential writes -- YMMV.
I'm usi...
AngularJS: How can I pass variables between controllers?
...
Solution without creating Service, using $rootScope:
To share properties across app Controllers you can use Angular $rootScope. This is another option to share data, putting it so that people know about it.
The preferred way to share some functionality across Contr...
How to avoid reinstalling packages when building Docker image for Python projects?
...from -r requirements.txt (line 1))
Running setup.py (path:/tmp/pip_build_root/pytest/setup.py) egg_info for package pytest
....
Cleaning up...
---> bf5c154b87c9
Removing intermediate container 08188205e92b
Step 4 : ADD . /srv
---> 3002a3a67e72
Removing intermediate container 83defd1851d0
Ste...
How to get Erlang's release version number from a shell?
...nt machine:
erl -eval '{ok, Version} = file:read_file(filename:join([code:root_dir(), "releases", erlang:system_info(otp_release), "OTP_VERSION"])), io:fwrite(Version), halt().' -noshell
This reads from the appropriate file, as described in the docs.
...
Is it possible to declare a variable in Gradle usable in Java?
... %c - %m%n</pattern>
</layout>
</appender>
<root level="info">
<appender-ref ref="FILE"/>
</root>
</configuration>
Files:
build.gradle
src/main/java/example/HelloWorld.java
src/test/java/example/HelloWorldTest.java
src/test/resources/logb...
Primary key or Unique index?
...hen it tries to insert the value 1 into this column for a second time.
In MySQL a unique constraint allows multiple NULLs.
It is possible to make a unique index on mutiple columns.
Primary key versus unique index
Things that are the same:
A primary key implies a unique index.
Things that are...
Which is the preferred way to concatenate a string in Python?
...rns. And this is just yet another reason why premature optimization is the root of all evil. Don't use a technique that's supposed "faster" unless you first measure it.
Therefore the "best" version to do string concatenation is to use + or +=. And if that turns out to be slow for you, which is pret...
How can I change the copyright template in Xcode 4?
... company set up in your profile), let's change it.
Click on your project root in the Project Navigator on the left
Enable your Utilities view on the right while the project root is highlighted
Select the File Inspector, while the Identity displays your Project Name.
Under Project Document is a tex...