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Difference between java.lang.RuntimeException and java.lang.Exception
...ns that can be prevented programmatically. E.g NullPointerException, ArrayIndexOutOfBoundException. If you check for null before calling any method, NullPointerException would never occur. Similarly ArrayIndexOutOfBoundException would never occur if you check the index first. RuntimeException are n...
What does this square bracket and parenthesis bracket notation mean [first1,last1)?
...lements
How does this relate to Mathematics and Computer Science?
Array indexes tend to use a different offset depending on which field are you in:
Mathematics tends to be one-based.
Certain programming languages tends to be zero-based, such as C, C++, Javascript, Python, while other languages ...
How do I make Git ignore file mode (chmod) changes?
...case it may be necessary
to set this variable to false. See git-update-index(1).
The default is true (when core.filemode is not specified
in the config file).
The -c flag can be used to set this option for one-off commands:
git -c core.fileMode=false diff
And the --global flag wil...
What's the 'Ruby way' to iterate over two arrays at once
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Is there a way to get the index inside the loop shown above?
– Biju
Dec 25 '18 at 10:38
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Fix a Git detached head?
...e you have changed a file and want to restore it to the state it is in the index, don't delete the file first, just do
git checkout -- path/to/foo
This will restore the file foo to the state it is in the index.
If you want to keep your changes associated with the detached HEAD
Run git branch tmp -...
How is Python's List Implemented?
...
It's a dynamic array. Practical proof: Indexing takes (of course with extremely small differences (0.0013 µsecs!)) the same time regardless of index:
...>python -m timeit --setup="x = [None]*1000" "x[500]"
10000000 loops, best of 3: 0.0579 usec per loop
...&...
What is BSON and exactly how is it different from JSON?
...sing BSON encoding on top of JSON, MongoDB gets the capability of creating indexes on top of values that resides inside the JSON document in raw format. This helps in running efficient analytical queries as NoSQL system were known for having no support for Indexes.
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Replace multiple strings with multiple other strings
...ction.
The +n-1 converts the string to the number then 1 is subtracted to index the pets array.
The %number is then replaced with the string at the array index.
The /g causes the lambda function to be called repeatedly with each number which is then replaced with a string from the array.
In mode...
MySQL “Group By” and “Order By”
...Y fromEmail, timestamp
In order for the query to run efficiently, proper indexing is required.
Note that for simplification purposes, I've removed the LOWER(), which in most cases, won't be used.
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How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...(Updated - Thanks to the people who commented)
Modern Versions of PostgreSQL
Suppose you have a table named test1, to which you want to add an auto-incrementing, primary-key id (surrogate) column. The following command should be sufficient in recent versions of PostgreSQL:
ALTER TABLE test1 AD...