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Querying DynamoDB by date
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Updated Answer:
DynamoDB allows for specification of secondary indexes to aid in this sort of query. Secondary indexes can either be global, meaning that the index spans the whole table across hash keys, or local meaning that the index would exist within each hash key partition, thus re...
Permutations in JavaScript?
...input) {
function permutate(array, callback) {
function p(array, index, callback) {
function swap(a, i1, i2) {
var t = a[i1];
a[i1] = a[i2];
a[i2] = t;
}
if (index == array.length - 1) {
callback(a...
How do servlets work? Instantiation, sessions, shared variables and multithreading
...up" value is absent, the init() method will be invoked whenever the HTTP request hits that servlet for the very first time.
When the servlet container is finished with all of the above described initialization steps, then the ServletContextListener#contextInitialized() will be invoked.
When the s...
A list of indices in MongoDB?
... in mongodb in shell? i read through http://www.mongodb.org/display/DOCS/Indexes but i dont see anything
6 Answers
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In plain English, what does “git reset” do?
...urrent branch and reset it to point somewhere else, and possibly bring the index and work tree along. More concretely, if your master branch (currently checked out) is like this:
- A - B - C (HEAD, master)
and you realize you want master to point to B, not C, you will use git reset B to move it t...
Does Python have a string 'contains' substring method?
I'm looking for a string.contains or string.indexof method in Python.
10 Answers
1...
Return index of greatest value in an array
...y the best way, since it’s reliable and works on old browsers:
function indexOfMax(arr) {
if (arr.length === 0) {
return -1;
}
var max = arr[0];
var maxIndex = 0;
for (var i = 1; i < arr.length; i++) {
if (arr[i] > max) {
maxIndex = i;
...
Iterator Loop vs index loop [duplicate]
...it's only one out of four distinct ways to iterate over a std::vector:
1) index-based iteration
for (std::size_t i = 0; i != v.size(); ++i) {
// access element as v[i]
// any code including continue, break, return
}
Advantages: familiar to anyone familiar with C-style code, can loop usi...
Is it possible to set the stacking order of pseudo-elements below their parent element? [duplicate]
...tacking order.
Positioning the pseudo-element (absolute) and assigning a z-index value other than “auto” creates the new stacking context.
#element {
position: relative; /* optional */
width: 100px;
height: 100px;
background-color: blue;
}
#element::after {
co...
Checking if a field contains a string
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Note that this will not make efficient use of an index and result in all values being scanned for matches. See the notes on Regular Expressions
– Stennie
Jul 18 '12 at 20:54
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