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What is the minimum valid JSON?
...a JSON text as being a serialized object or array.
This means that only {} and [] are valid, complete JSON strings in parsers and stringifiers which adhere to that standard.
However, the introduction of ECMA-404 changes that, and the updated advice can be read here. I've also written a blog post on ...
How important is the order of columns in indexes?
... Also keep in mind, suppose your Index is like the picture above, and your query filters on column1 and column2, but column2 is more unique and what you really want to filter on is actually column2, then its more beneficial to just have a index where column 2 is first. This may seem counte...
How to find where a method is defined at runtime?
...d occurred, a backend process failed to run. Now, we were good little boys and girls and ran rake test after every check-in but, due to some oddities in Rails' library loading, it only occurred when we ran it directly from Mongrel in production mode.
...
Why does one hot encoding improve machine learning performance?
...ced that when One Hot encoding is used on a particular data set (a matrix) and used as training data for learning algorithms, it gives significantly better results with respect to prediction accuracy, compared to using the original matrix itself as training data. How does this performance increase h...
What's the difference between lists and tuples?
...cture, lists have order.
Using this distinction makes code more explicit and understandable.
One example would be pairs of page and line number to reference locations in a book, e.g.:
my_location = (42, 11) # page number, line number
You can then use this as a key in a dictionary to store not...
What is a Context Free Grammar?
...to me what a context free grammar is? After looking at the Wikipedia entry and then the Wikipedia entry on formal grammar, I am left utterly and totally befuddled. Would someone be so kind as to explain what these things are?
...
difference between socket programming and Http programming
What is the difference between socket programming and Http programming? can anyone help please?
5 Answers
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SQL SELECT WHERE field contains words
...e present, use this:
SELECT * FROM mytable
WHERE column1 LIKE '%word1%'
AND column1 LIKE '%word2%'
AND column1 LIKE '%word3%'
If you want something faster, you need to look into full text search, and this is very specific for each database type.
...
Extract file basename without path and extension in bash [duplicate]
...
You don't have to call the external basename command. Instead, you could use the following commands:
$ s=/the/path/foo.txt
$ echo "${s##*/}"
foo.txt
$ s=${s##*/}
$ echo "${s%.txt}"
foo
$ echo "${s%.*}"
foo
Note that this solution should work in all recent (post 2004) POS...
How can I pipe stderr, and not stdout?
I have a program that writes information to stdout and stderr , and I need to grep through what's coming to stderr , while disregarding stdout .
...