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postgresql return 0 if returned value is null
...price DESC ) FROM web_price_scan
WHERE listing_Type = 'AARM'
AND u_kbalikepartnumbers_id = 1000307
AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
AND COALESCE( price, 0 ) > ( SELECT AVG( COALESCE( price, 0 ) )* 0.50
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What is the difference between iterator and iterable and how to use them?
I am new in Java and I'm really confused with iterator and iterable. Can anyone explain to me and give some examples?
13 An...
How do I toggle an element's class in pure JavaScript?
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2014 answer: classList.toggle() is the standard and supported by most browsers.
Older browsers can use use classlist.js for classList.toggle():
var menu = document.querySelector('.menu') // Using a class instead, see note below.
menu.classList.toggle('hidden-phon...
Add custom messages in assert?
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Another option is to reverse the operands and use the comma operator. You need extra parentheses so the comma isn't treated as a delimiter between the arguments: assert(("A must be equal to B", a == b));
– Keith Thompson
J...
Finding duplicate values in a SQL table
...T(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attrib...
Check whether a string is not null and not empty
How can I check whether a string is not null and not empty?
31 Answers
31
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What is best tool to compare two SQL Server databases (schema and data)? [duplicate]
...ike to compare two SQL Server databases including schema (table structure) and data in tables too. What is best tool to do this?
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Convert hex string to int in Python
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x = int("deadbeef", 16)
With the 0x prefix, Python can distinguish hex and decimal automatically.
>>> print int("0xdeadbeef", 0)
3735928559
>>> print int("10", 0)
10
(You must specify 0 as the base in order to invoke this prefix-guessing behavior; omitting the second paramet...
Why do variable names often start with the letter 'm'? [duplicate]
Looking at the Android tutorials such as the Notepad tutorial , I noticed that almost all variables are named starting with the letter 'm'. What convention is this, and where does it originate from?
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iOS - Dismiss keyboard when touching outside of UITextField
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You'll need to add an UITapGestureRecogniser and assign it to the view, and then call resign first responder on the UITextField on it's selector.
The code:
In viewDidLoad
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@select...