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Differences between C++ string == and compare()?
...code in Release environment, both are pretty much the same.
FYI, I ran 1,000,000 iteration in order to come up with such conclusion.
In order to prove why in debug environment the string::compare is faster, I went to the assembly and here is the code:
DEBUG BUILD
string::operator==()
i...
How to store a dataframe using Pandas
...HDF5 storage format
In their experiment, they serialize a DataFrame of 1,000,000 rows with the two columns tested separately: one with text data, the other with numbers. Their disclaimer says:
You should not trust that what follows generalizes to your data. You should look at your own data and...
What data type to use for money in Java? [closed]
...
Many banks handle far larger sums of money that $20,000,000 every day. This does not even take account of currencies like yen with large exchange rates to the dollar. Integer types may be best to avoid rounding problems although they get messy with interest and exchange rate...
Most efficient T-SQL way to pad a varchar on the left to a certain length?
...t very efficient in terms of execution time. The Tally table I used has 64,000 records. Kudos to Martin Smith for pointing out execution time efficiency.
SET STATISTICS TIME ON
select FORMAT(N, 'd10') as padWithZeros from Tally
SET STATISTICS TIME OFF
SQL Server Execution Times:
CPU time = 21...
Make a DIV fill an entire table cell
...eight: 1px;">
<td style="height: inherit; border: 1px solid #000; width: 100px;">
<div>
Something big with multi lines and makes table bigger
</div>
</td>
<td style="height: inherit; border: 1px solid #000; w...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...cided to create benchmarks myself.
I created a very simple table with 500,000 rows:
CREATE TABLE test(
ID INT(11) DEFAULT NULL,
Description VARCHAR(20) DEFAULT NULL
)
ENGINE = INNODB
CHARACTER SET utf8
COLLATE utf8_general_ci;
Then I filled it with random data by running this stored procedur...
CSS hexadecimal RGBA?
...and ff represent a fully opaque color.
Example 3In other words, #0000ffcc represents the same color as rgba(0, 0, 100%, 80%) (a slightly-transparent blue).
4 digits
This is a shorter variant of the 8-digit notation, "expanded" in the same way as the 3-digit notation is. The fi...
How do I increase the scrollback buffer in a running screen session?
...
Press Ctrl-a then : and then type
scrollback 10000
to get a 10000 line buffer, for example.
You can also set the default number of scrollback lines by adding
defscrollback 10000
to your ~/.screenrc file.
To scroll (if your terminal doesn't allow you to by default)...
Add EBS to Ubuntu EC2 Instance
... (with update to /etc/fstab so it stays mounted on reboot):
sudo mkdir -m 000 /vol
echo "/dev/xvdf /vol auto noatime 0 0" | sudo tee -a /etc/fstab
sudo mount /vol
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MongoDB or CouchDB - fit for production? [closed]
...gs including real time analytics and a caching layer. They are doing over 1000 writes per second to a fairly large database.
If you go to the mongodb Production Deployments page you'll see some people who are using mongo in production.
If you have any questions about the scale or scope of producti...