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How do I modify fields inside the new PostgreSQL JSON datatype?
With postgresql 9.3 I can SELECT specific fields of a JSON data type, but how do you modify them using UPDATE? I can't find any examples of this in the postgresql documentation, or anywhere online. I have tried the obvious:
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Graph Algorithm To Find All Connections Between Two Arbitrary Vertices
I am trying to determine the best time efficient algorithm to accomplish the task described below.
16 Answers
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Zip lists in Python
...y elements. Each element is a three-tuple.
See for yourself:
In [1]: a = b = c = range(20)
In [2]: zip(a, b, c)
Out[2]:
[(0, 0, 0),
(1, 1, 1),
...
(17, 17, 17),
(18, 18, 18),
(19, 19, 19)]
To find out how many elements each tuple contains, you could examine the length of the first element...
difference between foldLeft and reduceLeft in Scala
I have learned the basic difference between foldLeft and reduceLeft
7 Answers
7
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Curious null-coalescing operator custom implicit conversion behaviour
Note: this appears to have been fixed in Roslyn
5 Answers
5
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PHP append one array to another (not array_push or +)
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array_merge is the elegant way:
$a = array('a', 'b');
$b = array('c', 'd');
$merge = array_merge($a, $b);
// $merge is now equals to array('a','b','c','d');
Doing something like:
$merge = $a + $b;
// $merge now equals array('a','b')
Will not work, because the + operat...
On a CSS hover event, can I change another div's styling? [duplicate]
When I hover over a div or class with an id of "a", can I get the background color of a div or class with the id of "b" to change?
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How to do exponential and logarithmic curve fitting in Python? I found only polynomial fitting
I have a set of data and I want to compare which line describes it best (polynomials of different orders, exponential or logarithmic).
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sprintf like functionality in Python
I would like to create a string buffer to do lots of processing, format and finally write the buffer in a text file using a C-style sprintf functionality in Python. Because of conditional statements, I can’t write them directly to the file.
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Trying to embed newline in a variable in bash [duplicate]
...ine in the source code
p="${var1}
${var2}"
echo "${p}"
Using $'\n' (only bash and zsh)
p="${var1}"$'\n'"${var2}"
echo "${p}"
Details
1. Inserting \n
p="${var1}\n${var2}"
echo -e "${p}"
echo -e interprets the two characters "\n" as a new line.
var="a b c"
first_loop=true
for i in $var
do
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