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How to select date from datetime column?
...20' has performance issues. As stated here:
it will calculate DATE() for all rows, including those that don't match.
it will make it impossible to use an index for the query.
Use BETWEEN or >, <, = operators which allow to use an index:
SELECT * FROM data
WHERE datetime BETWEEN '2009-10-...
MYSQL OR vs IN performance
...than using OR.
Do not believe people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache):
IN: 2.34969592094s
OR: 5.83781504631s
Update:
(I don't have the source code for the original test, as it...
docker mounting volumes on host
...independent of the container's life cycle. Docker therefore never automatically delete volumes when you remove a container, nor will it "garbage collect" volumes that are no longer referenced by a container." One of these statements must be wrong.
– mc0e
May 6...
java.util.Date vs java.sql.Date
...ns, you've hit my favorite pet peeve with JDBC: Date class handling.
Basically databases usually support at least three forms of datetime fields which are date, time and timestamp. Each of these have a corresponding class in JDBC and each of them extend java.util.Date. Quick semantics of each of th...
How do I force “git pull” to overwrite local files?
... content), these files will not be affected.
First, run a fetch to update all origin/<branch> refs to latest:
git fetch --all
Then, you have two options:
git reset --hard origin/master
OR If you are on some other branch:
git reset --hard origin/<branch_name>
Explanation:
git fetch do...
Error: request entity too large
...
I had the same error recently, and all the solutions I've found did not work.
After some digging, I found that setting app.use(express.bodyParser({limit: '50mb'})); did set the limit correctly.
When adding a console.log('Limit file size: '+limit); in node_m...
Hash collision in git
What would actually happen if I had a hash collision while using git?
9 Answers
9
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HTTP POST with URL query parameters — good idea or not? [closed]
...a command to the resource to limit the scope of the current request. Typically, query strings are used to sort or filter a GET request (like ?page=1&sort=title) but I suppose it makes sense on a POST to also limit the scope (perhaps like ?action=delete&id=5).
...
Changing API level Android Studio
...fileTree(dir: 'libs', include: ['*.jar'])
}
Sync gradle button (refresh all gradle projects also works)
For beginners in Android Studio "Sync gradle button" is located in
Tools -> Android -> Sync Project with Gradle Files "Rebuild project"
Build -> Rebuild Project
Rebuild pro...
Android Studio 0.4 Duplicate files copied in APK META-INF/LICENSE.txt
...ependencies.txt'
exclude 'META-INF/LGPL2.1'
}
}
EDIT: Almost all OS licence include the obligation to "include a copy of the licence" into your project. So this means, that you have to include a copy of all OS licences you use into you projects. By "excluding" them in gradle, you viola...