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Global Git ignore
... doing:
git config --global core.excludesFile
The result should be the expanded path to your user profile's .gitignore. Ensure that the value does not contain the unexpanded %USERPROFILE% string.
Important: The above commands will only set the location of the ignore file that git will use. The file...
Equivalent of LIMIT and OFFSET for SQL Server?
In PostgreSQL there is the Limit and Offset keywords which will allow very easy pagination of result sets.
16 Answers
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MySQL Query GROUP BY day / month / year
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GROUP BY YEAR(record_date), MONTH(record_date)
Check out the date and time functions in MySQL.
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How do I create a variable number of variables?
...u can use dictionaries to accomplish this. Dictionaries are stores of keys and values.
>>> dct = {'x': 1, 'y': 2, 'z': 3}
>>> dct
{'y': 2, 'x': 1, 'z': 3}
>>> dct["y"]
2
You can use variable key names to achieve the effect of variable variables without the security ris...
How many random elements before MD5 produces collisions?
... quintillion 374 quadrillion 607 trillion 431 billion 768 million 211 thousand 456.
However if you keep all the hashes then the probability is a bit higher thanks to birthday paradox. To have a 50% chance of any hash colliding with any other hash you need 264 hashes. This means that to get a collis...
Realistic usage of the C99 'restrict' keyword?
I was browsing through some documentation and questions/answers and saw it mentioned. I read a brief description, stating that it would be basically a promise from the programmer that the pointer won't be used to point somewhere else.
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Query-string encoding of a Javascript Object
Do you know a fast and simple way to encode a Javascript Object into a string that I can pass via a GET Request?
40 Ans...
Skip List vs. Binary Search Tree
...node need to be locked.
Update from Jon Harrops comments
I read Fraser and Harris's latest paper Concurrent programming without locks. Really good stuff if you're interested in lock-free data structures. The paper focuses on Transactional Memory and a theoretical operation multiword-compare-an...
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How to get the sizes of the tables of a MySQL database?
...n MB`
FROM information_schema.TABLES
WHERE table_schema = "$DB_NAME"
AND table_name = "$TABLE_NAME";
or this query to list the size of every table in every database, largest first:
SELECT
table_schema as `Database`,
table_name AS `Table`,
round(((data_length + index_length...