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Difference between partition key, composite key and clustering key in Cassandra?
...KEY:
insert into stackoverflow_simple (key, data) VALUES ('han', 'solo');
select * from stackoverflow_simple where key='han';
table content
key | data
----+------
han | solo
COMPOSITE/COMPOUND KEY can retrieve "wide rows" (i.e. you can query by just the partition key, even if you have clusteri...
Determining if an Object is of primitive type
...uto-boxing. The compiler does this itself. When it sees an opportunity, it converts a primitive type into its appropriate wrapper class.
What is probably happening here is when you declare
Object o = i;
The compiler will compile this statement as saying
Object o = Integer.valueOf(i);
This is ...
Create a table without a header in Markdown
... Windows application.
ParseDown Extra: A parser in PHP.
Pandoc: A document converter for the command line written in Haskell (supports header-less tables via its simple_tables and multiline_tables extensions)
Flexmark: A parser in Java.
CSS solution
If you're able to change the CSS of the HTML ou...
How to use Python's pip to download and keep the zipped files for a package?
...rent working directory by default), but it performs the additional step of converting any source packages to wheels.
It conveniently supports requirements files:
pip wheel -r requirements.txt -w .\outputdir
Add the --no-deps argument if you only want the specifically requested packages:
pip whe...
How to delete files older than X hours
...
For SunOS 5.10
Example 6 Selecting a File Using 24-hour Mode
The descriptions of -atime, -ctime, and -mtime use the ter-
minology n ``24-hour periods''. For example, a file accessed
at 23:59 is selected by:
example% find . -atime -1 -print...
missing private key in the distribution certificate on keychain
...ain Access application to export both the certificate and the private key. Select both using shift or command and right click to export to a .p12 file.
Attached a screenshot to make it very clear.
On your mac, import that .p12 file and you are good to go (just make sure you have a valid provisioni...
Getting “CHECKOUT can only be performed on a version resource” when trying to commit using Eclipse s
...om my project (by right clicking on the project from the package explorer, selecting "Team" -> "Commit"), I get the error:
...
How to parse a string into a nullable int
...bject value)
{
try { return (T)System.ComponentModel.TypeDescriptor.GetConverter(typeof(T)).ConvertFrom(value.ToString()); }
catch { return default(T); }
}
This approach can still be used for non-nullable parses as well as nullable:
enum Fruit { Orange, Apple }
var res1 = Parse<Fruit&g...
Zip lists in Python
...
@Sigur: "Convert tuple to list and back "
– David Cary
Aug 29 '17 at 11:47
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Import multiple csv files into pandas and concatenate into one DataFrame
...aframe API. If all the data fits into memory, you can call df.compute() to convert the dataframe into a Pandas dataframe.
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