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Storing time-series data, relational or non?
...n is never a Key (duplicate rows, which are prohibited in a Relational database, must be prevented by other means).
The Id column requires an additional Index, which obviously impedes the speed of INSERT/DELETE, and adds to the disk space used.
You can get rid of it. Please.
Elevation
Now ...
Best practices for adding .gitignore file for Python projects? [closed]
...alled.cfg
bin
develop-eggs
dist
downloads
eggs
parts
src/*.egg-info
lib
lib64
Thanks to Jacob Kaplan-Moss
Also I tend to put .svn in since we use several SCM-s where I work.
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Why does using an Underscore character in a LIKE filter give me all the results?
...ess supports like operator. My solution will work in most, if not all, databases.
– Rachcha
Oct 25 '13 at 13:51
2
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How to make Eclipse behave well in the Windows 7 taskbar?
... At first neither option was working for me (Eclipse 4.2 32 bit, Windows 7 64 bit, JDK 1.6 32 bit). Then I tried the following: 1. Right click on eclipse.exe -> Properties -> Compatibility, enable compatibility mode with Windows XP Service Pack 3. 2. Run Eclipse. 3. Wait until the workspace i...
In-memory size of a Python structure
...s there a reference for the memory size of Python data stucture on 32- and 64-bit platforms?
7 Answers
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How to find the mysql data directory from command line in windows
...----+
| basedir | /usr/local/mysql-5.7.17-macos10.12-x86_64/ |
| character_sets_dir | /usr/local/mysql-5.7.17-macos10.12-x86_64/share/charsets/ |
| datadir | /usr/local/mysql/data/ |
| innodb_data_home_dir ...
How to serialize an object into a string
...t. I would like to serialize the object into a string and store into a database instead. Can anyone help me?
13 Answers
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What does static_assert do, and what would you use it for?
...t;typename T, typename U>
struct Type
{
BOOST_STATIC_ASSERT(boost::is_base_of<T, Interface>::value);
BOOST_STATIC_ASSERT(std::numeric_limits<U>::is_integer);
/* ... more code ... */
};
This will cause a compile time error if any of the above conditions are not met.
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Extracting just Month and Year separately from Pandas Datetime column
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Note that the resulting column is not of the datetime64 dtype anymore. Using df.my_date_column.astype('datetime64[M]'), as in @Juan's answer converts to dates representing the first day of each month.
– Nickolay
May 26 '18 at 19:52
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C++ Best way to get integer division and remainder
...imize, though, at least for g++. A simple experiment with g++ 6.3.0 on x86_64 revealed that with no optimization at all, you get two idivl instructions, but with -O1 or greater, you get one. As the manual says, “Without any optimization option … Statements are independent”.
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