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Why does Oracle 9i treat an empty string as NULL?
...'t do much to tell me why this is the case. As I understand the SQL specifications, ' ' is not the same as NULL -- one is a valid datum, and the other is indicating the absence of that same information.
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window.location.reload with clear cache [duplicate]
...o your head:
<meta http-equiv="Cache-control" content="no-cache">
If you want to remove the document from cache, expires meta tag should work to delete it by setting its content attribute to -1 like so:
<meta http-equiv="Expires" content="-1">
http://www.metatags.org/meta_http_equi...
How to have an automatic timestamp in SQLite?
...rged your answer and javed's. With DEFAULT (STRFTIME('%Y-%m-%d %H:%M:%f', 'NOW', 'localtime')) one actually gets meaningful microsecond values.
– Dietmar
Jun 22 '17 at 18:24
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Creating and Update Laravel Eloquent
What's the shorthand for inserting a new record or updating if it exists?
13 Answers
1...
What is the difference between a.getClass() and A.class in Java?
...that there would be performance or other subtle benefits to using both in different circumstances (just like there are with Class.forName() and ClassLoader.loadClass() .
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Ukkonen's suffix tree algorithm in plain English
...e an initial tree, which looks like this:
And what it means is this:
Now we progress to position 2 (right after b). Our goal at each step
is to insert all suffixes up to the current position. We do this
by
expanding the existing a-edge to ab
inserting one new edge for b
In our representati...
Can I bind an array to an IN() condition?
I'm curious to know if it's possible to bind an array of values to a placeholder using PDO. The use case here is attempting to pass an array of values for use with an IN() condition.
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Duplicate log output when using Python logging module
...r = logging.getLogger(name)
logger.setLevel(logging.DEBUG)
now = datetime.datetime.now()
handler = logging.FileHandler(
'/root/credentials/Logs/ProvisioningPython'
+ now.strftime("%Y-%m-%d")
+ '.log')
formatter = logging.Formatter...
How to print number with commas as thousands separators?
...ython ≥2.7
f'{value:n}' # For Python ≥3.6
Reference
Per Format Specification Mini-Language,
The ',' option signals the use of a comma for a thousands separator. For a locale aware separator, use the 'n' integer presentation type instead.
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Automatic creation date for Django model form objects?
...
You can use the auto_now and auto_now_add options for updated_at and created_at respectively.
class MyModel(models.Model):
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
...