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Optimise PostgreSQL for fast testing
...d memory limit if you increase shared_buffers on PostgreSQL 9.2 and below; 9.3 and above changed how they use shared memory to avoid that.
If you're using a just a couple of connections that do lots of work, increase work_mem to give them more RAM to play with for sorts etc. Beware that too high a ...
How do I get currency exchange rates via an API such as Google Finance? [closed]
...weekend. Doesn't require any kind of sign up.
[http://query.yahooapis.com/v1/public/yql?q=select * from yahoo.finance.xchange where pair in ("USDEUR", "USDJPY", "USDBGN", "USDCZK", "USDDKK", "USDGBP", "USDHUF", "USDLTL", "USDLVL", "USDPLN", "USDRON", "USDSEK", "USDCHF", "USDNOK", "USDHRK", "USDRUB"...
SecItemAdd and SecItemCopyMatching returns error code -34018 (errSecMissingEntitlement)
...as under memory pressure. We believe these problems
were resolved in iOS 9.3.
We suspect that there may be yet more causes
of this problem.
So, if you see this problem on a user device (one
that hasn’t been talked to by Xcode) that’s running iOS 9.3 or later,
please do file a...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...'s an example of this in the documentation: http://www.postgresql.org/docs/9.3/static/plpgsql-control-structures.html, example 40-2 right at the bottom.
That's usually the easiest way. You can do some magic with rules, but it's likely going to be a lot messier. I'd recommend the wrap-in-function ap...
What is INSTALL_PARSE_FAILED_NO_CERTIFICATES error?
...V2 scheme signs the entire APK rather than just the JAR, as is done in the V1 scheme. If you sign with only V2, and attempt to install on a pre-7.0 target, you'll get this error since the JARs themselves are not signed and the pre-7.0 PackageManager cannot detect the presence of the V2 APK signatur...
How to directly initialize a HashMap (in a literal way)?
...
can you add "as ImmutableMap.builder.put("k1","v1").put("k2","v2").build()" as the "of" method is limited to 5 pairs at maximum ?
– kommradHomer
Oct 15 '14 at 9:15
...
How to create a new branch from a tag?
...like to create a new master branch from an existing tag. Say I have a tag v1.0 . How to create a new branch from this tag?
...
How to install Xcode Command Line Tools
... Xcode 9.4
- (Command Line Tool (Xcode 9.4) - for macOS 10.13)
Xcode 9.3.1
Xcode 9.3
- (Command Line Tool (Xcode 9.3) - for macOS 10.13)
Xcode 9.2
- (Command Line Tool (Xcode 9.2) - for macOS 10.13)
- (Command Line Tool (Xcode 9.2) - for macOS 10.12)
Xcode 9.1
- (Command Line Too...
Initializing a two dimensional std::vector
...nt to initialise a 2 D vector with 0;
vector<vector<int>> v1(5, vector<int>(3,0));
for(int i=0;i<v1.size();i++)
{
for(int j=0;j<v1[i].size();j++)
cout<<v1[i][j]<<" ";
cout<<endl;
}
}
...
Add new row to dataframe, at specific row-index, not appended?
...F[r,] <- newrow
existingDF
}
> insertRow(existingDF, newrow, r)
V1 V2 V3 V4
1 1 6 11 16
2 2 7 12 17
3 1 2 3 4
4 3 8 13 18
5 4 9 14 19
6 5 10 15 20
If speed is less important than clarity, then @Simon's solution works well:
existingDF <- rbind(existingDF[1:r,],newrow,exi...