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Is a Java hashmap search really O(1)?
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128
A particular feature of a HashMap is that unlike, say, balanced trees, its behavior is probabil...
In Postgresql, force unique on combination of two columns
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239
CREATE TABLE someTable (
id serial primary key,
col1 int NOT NULL,
col2 int NOT NU...
How to add onload event to a div element
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24 Answers
24
Active
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“Variable” variables in Javascript?
...roblem.
If you have a fixed set of names, such as
// BAD
var foo = 42;
var bar = 21;
var key = 'foo';
console.log(eval(key));
store the those name/values as properties of an object and use bracket notation to look them up dynamically:
// GOOD
var obj = {
foo: 42,
bar: ...
How do I set vertical space between list items?
...red Oct 8 '13 at 17:31
user1633525user1633525
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Performance - Date.now() vs Date.getTime()
...y; performance is a little better with .now()):
var t1 = Date.now();
var t2 = new Date().getTime();
However, the time value from any already-created Date instance is frozen at the time of its construction (or at whatever time/date it's been set to). That is, if you do this:
var now = new Date();...
LAST_INSERT_ID() MySQL
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251
You could store the last insert id in a variable :
INSERT INTO table1 (title,userid) VALUES (...
How to support placeholder attribute in IE8 and 9
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answered Feb 22 '13 at 9:32
red_alertred_alert
1,7201414 silver badges2323 bronze badges
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JavaScript: how to change form action attribute value based on selection?
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277
$("#selectsearch").change(function() {
var action = $(this).val() == "people" ? "user" : "co...
Open a file with Notepad in C#
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edited Jun 4 '14 at 11:52
mihai
3,77333 gold badges2222 silver badges4040 bronze badges
answered Oct 2...