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How to remove leading and trailing whitespace in a MySQL field?
...ne of the current answers will actually remove 100% of whitespace from the start and end of a string.
As mentioned in other posts, the default TRIM only removes spaces - not tabs, formfeeds etc. A combination of TRIMs specifying other whitespace characters may provide a limited improvement e.g. TRI...
Colon (:) in Python list index [duplicate]
...the delimiter of the slice syntax to 'slice out' sub-parts in sequences , [start:end]
[1:5] is equivalent to "from 1 to 5" (5 not included)
[1:] is equivalent to "1 to end"
[len(a):] is equivalent to "from length of a to end"
Watch https://youtu.be/tKTZoB2Vjuk?t=41m40s at around 40:00 he starts e...
Checking whether a string starts with XXXX
I would like to know how to check whether a string starts with "hello" in Python.
4 Answers
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“Cannot send session cache limiter - headers already sent” [duplicate]
...problem with sessions which is becoming very annoying. Every time I try to start a session on a particular page I get the following error:
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Force the origin to start at 0
... bar to get left off the chart entirely (e.g. if its value is zero and you start the axis at zero), so you may not see it and may not even know it's there. I recommend plotting data in full first, inspect, then use the above tip to improve the plot's aesthetics.
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使用模拟器构建应用程序 · App Inventor 2 中文网
...stead of a real phone. Instead of connecting a phone to the USB port, just start the emulator program. When you click Connect to Phone in the Blocks Editor, your app will appear in the emulator.
You can’t do everything with the emulator that you can with a real phone — you can’t shake it, for...
Python - Create list with numbers between 2 values?
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x*increment, but what do you mean by 2*startvalue, what for? would you explain please?
– Santosa Sandy
Mar 27 '17 at 7:30
add a comment
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Fixing slow initial load for IIS
...nd D seem to be in the same category since they only influence the initial start time, they do warmup of the website like compilation and loading of libraries in memory.
Using C, setting the idle timeout, should be enough so that subsequent requests to the server are served fast (restarting the app...
Amazon EC2, mysql aborting start because InnoDB: mmap (x bytes) failed; errno 12
... I realized that the instance had basically zero free memory. So I tried restarting apache
sudo system httpd restart
sudo system mysqld restart
And everything worked fine. Maybe another solution is to configure apache to not eat up so much memory somehow.
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How to pass a user defined argument in scrapy spider
... = 'myspider'
def __init__(self, category='', **kwargs):
self.start_urls = [f'http://www.example.com/{category}'] # py36
super().__init__(**kwargs) # python3
def parse(self, response)
self.log(self.domain) # system
Taken from the Scrapy doc: http://doc.scrapy.o...