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Best way to check for “empty or null value”
What is best way to check if value is null or empty string in Postgres sql statements?
10 Answers
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Perforce for Git users? [closed]
There is a lot of "Git for Perforce users" documentation out there, but seemingly very little of the opposite.
3 Answers
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Determine the type of an object?
Is there a simple way to determine if a variable is a list, dictionary, or something else? I am getting an object back that may be either type and I need to be able to tell the difference.
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When and why are database joins expensive?
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Denormalising to improve performance? It sounds convincing, but it doesn't hold water.
Chris Date, who in company with Dr Ted Codd was the original proponent of the relational data model, ran out of patience with misinformed argumen...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
I have come across a situation (which I think is weird but is possibly quite normal) where I use the EntityManager.getReference(LObj.getClass(), LObj.getId()) to get a database entity and then pass the returned object to be persisted in another table.
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Difference between size_t and unsigned int?
...t . I have searched on the internet and everywhere mentioned that size_t is an unsigned type so, it can represent only non-negative values.
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Usages of Null / Nothing / Unit in Scala
...nnot complete normally by returning, it could throw an exception). Nothing is never instantiated and is there for the benefit of the type system (to quote James Iry: "The reason Scala has a bottom type is tied to its ability to express variance in type parameters."). From the article you linked to:
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MVC Vs n-tier architecture
I was wondering what exactly is the difference between MVC(which is an architectural pattern) and an n-tier architecture for an application. I searched for it but couldn't find a simple explanation. May be I am a bit naive on MVC concepts, so if anyone can explain the difference then it would be gre...
Nginx — static file serving confusion with root & alias
... from a directory without touching the app server. The nginx config I have is something like this...
7 Answers
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Why is there no xrange function in Python3?
...len=0)
1 loops, best of 3: 1.33 s per loop
Apparently, 3.x range really is a bit slower than 2.x xrange. And the OP's xrange function has nothing to do with it. (Not surprising, as a one-time call to the __iter__ slot isn't likely to be visible among 10000000 calls to whatever happens in the loop...