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What is the recommended way to delete a large number of items from DynamoDB?
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The link to BatchWriteItem is now docs.aws.amazon.com/amazondynamodb/latest/APIReference/…
– Tony
Jan 10 '17 at 15:18
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Python date string to date object
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Directly related question:
What if you have
datetime.datetime.strptime("2015-02-24T13:00:00-08:00", "%Y-%B-%dT%H:%M:%S-%H:%M").date()
and you get:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/local/li...
How do you increase the max number of concurrent connections in Apache?
...2 process can service only 50 concurrent connections/clients i.e. 25x2=50. Now if more concurrent users comes, then another child process will start, that can service another 25 users. But how many child processes can be started is controlled by ServerLimit parameter, this means that in the configur...
Troubleshooting “Illegal mix of collations” error in mysql
... two strings of incompatible collation or by attempting to select data of different collation into a combined column.
The clause COLLATE allows you to specify the collation used in the query.
For example, the following WHERE clause will always give the error you posted:
WHERE 'A' COLLATE latin1_g...
How do I save and restore multiple variables in python?
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If you need to save multiple objects, you can simply put them in a single list, or tuple, for instance:
import pickle
# obj0, obj1, obj2 are created here...
# Saving the objects:
with open('objs.pkl', 'w') as f: # Python ...
Zooming MKMapView to fit annotation pins?
...nt to note that showAnnotations also adds the annotations to the map, even if an annotation for that location already exists.
– Eneko Alonso
Feb 29 '16 at 22:26
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What are file descriptors, explained in simple terms?
...dded great stuff. I will add just my 2 cents.
According to Wikipedia we know for sure: a file descriptor is a non-negative integer. The most important thing I think is missing, would be to say:
File descriptors are bound to a process ID.
We know most famous file descriptors are 0, 1 and 2.
0 co...
What are allowed characters in cookies?
...supported by browsers:
either the NAME or the VALUE may be empty strings
if there is no = symbol in the string at all, browsers treat it as the cookie with the empty-string name, ie Set-Cookie: foo is the same as Set-Cookie: =foo.
when browsers output a cookie with an empty name, they omit the equ...
How to solve javax.net.ssl.SSLHandshakeException Error?
...should be able to tell you exactly what to do for your specific browser.)
Now that you have the certificate saved in a file, you need to add it to your JVM's trust store. At $JAVA_HOME/jre/lib/security/ for JREs or $JAVA_HOME/lib/security for JDKs, there's a file named cacerts, which comes with Jav...
Summarizing multiple columns with dplyr? [duplicate]
...x. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
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