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If table exists drop table then create it, if it does not exist just create it
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What are “sugar”, “desugar” terms in context of Java 8?
...ugar is, in essence, syntactical (not all recent sweet additions were just compiler changes).
Here are a few examples :
the postfix and prefix increment operators (i++ and ++i). Their only purpose is to avoid writing an additional statement. They're pure sugar.
+=, |=, &=, etc. are made of t...
What is the difference between persist() and merge() in JPA and Hibernate?
...ied to an entity X are
as follows:
If X is a new entity, it
becomes managed. The entity X will be
entered into the database at or before
transaction commit or as a result of
the flush operation.
If X is a
preexisting managed entity, it is
ignored by the persist operation.
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The purpose of Model View Projection Matrix
...rom world space to camera space, projection from camera to screen.
If you compose all three, you can use the one result to map all the way from object space to screen space, making you able to work out what you need to pass on to the next stage of a programmable pipeline from the incoming vertex po...
How to append text to a text file in C++?
...close the file manually, as it does so upon destruction. See stackoverflow.com/questions/748014. Also, <iostream> is not being used in the example.
– swalog
Sep 12 '13 at 15:47
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Shading a kernel density plot between two points.
... ... that have been in demo(graphics) since before the dawn on time so one comes across every now and then. Same idea for NBER regression shading etc.
– Dirk Eddelbuettel
Aug 16 '10 at 17:19
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What is the difference between '>' and a space in CSS selectors?
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Selecting data frame rows based on partial string match in a column
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@nico: in fact, grep comes from the ed command g/re/p (global / regular expression / print), and it reveals its real power only to the master of regular expression-fu ;-): en.wikipedia.org/wiki/Grep
– Stephan Kolassa
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Anonymous recursive PHP functions
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@ellabeauty: No, you completely misunderstand it. Everything without & is by value. Everything with & is by reference. "Objects" are not values in PHP5 and cannot be assigned or passed. You are dealing with a variable whose value is an ob...