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What exactly are iterator, iterable, and iteration?
What is the most basic definition of "iterable", "iterator" and "iteration" in Python?
13 Answers
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PostgreSQL function for last inserted ID
...an id column created with the SERIAL pseudo-type. To avoid relying on this and to feel more clean, you can use instead pg_get_serial_sequence:
INSERT INTO persons (lastname,firstname) VALUES ('Smith', 'John');
SELECT currval(pg_get_serial_sequence('persons','id'));
Caveat: currval() only work...
Conversion of a datetime2 data type to a datetime data type results out-of-range value
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I changed my datacolumns and used typeof now... Further I found my problem. there was 1 datarow that contained a wrong date, which triggered the error
– Gerbrand
Aug 26 '09 at 5:46
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Convert Pandas column containing NaNs to dtype `int`
I read data from a .csv file to a Pandas dataframe as below. For one of the columns, namely id , I want to specify the column type as int . The problem is the id series has missing/empty values.
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Maven: How to include jars, which are not available in reps into a J2EE project?
...l repository. If you create a script with a Maven invocation for each file and keep it alongside the jars, you (and anyone else with access) can easily install the jars (and associated pom files) to their local repository.
For example:
mvn install:install-file -Dfile=/usr/jars/foo.jar -DpomFile=/u...
Logical Operators, || or OR?
... no "better" but the more common one is ||. They have different precedence and || would work like one would expect normally.
See also: Logical operators (the following example is taken from there):
// The result of the expression (false || true) is assigned to $e
// Acts like: ($e = (false || true...
What do the different readystates in XMLHttpRequest mean, and how can I use them?
XMLHttpRequest has 5 readyState s, and I only use 1 of them (the last one, 4 ).
5 Answers
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Why doesn't String switch statement support a null case?
...wondering why the Java 7 switch statement does not support a null case and instead throws NullPointerException ? See the commented line below (example taken from the Java Tutorials article on switch ):
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How does Hadoop process records split across block boundaries?
...nteresting question, I spent some time looking at the code for the details and here are my thoughts. The splits are handled by the client by InputFormat.getSplits, so a look at FileInputFormat gives the following info:
For each input file, get the file length, the block size and calculate the spli...
Is cout synchronized/thread-safe?
...ate locking. However, do things like cout get special treatment in the standard library?
4 Answers
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