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PostgreSQL: insert from another table
I'm trying to insert data to a table from another table and the tables have only one column in common. The problem is, that the TABLE1 has columns that won't accept null values so I can't leave them empty and I can't get them from the TABLE2.
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Simple calculations for working with lat/lon and km distance?
...ie on the same line of longitude (north/south), they lie on a great circle and the conversion factor is just the Earth's polar circumference divided by 360 degrees. But it's different for east-west measurements, because (except for the equator) you're not measuring along a "great circle", so the "c...
Reading GHC Core
...re is GHC's intermediate language. Reading Core can help you better understand the performance of your program. Someone asked me for documentation or tutorials on reading Core, but I couldn't find much.
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What's a 3D doing in this HTML?
...esented as ASCII for email transportation.
In quoted-printable, any non-standard email octets are represented as an = sign followed by two hex digits representing the octet's value. Of course, to represent a plain = in email, it needs to be represented using quoted-printable encoding too: 3D are th...
difference between collection route and member route in ruby on rails?
What is the difference between collection routes and member routes in Rails?
4 Answers
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How to do a LIKE query in Arel and Rails?
...(users[:name].matches("%#{params[:user_name]}%")), I tried TRUNCATE users; and other such queries and nothing happened on the sql side. Looks safe to me.
– earlonrails
Aug 28 '13 at 18:56
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How to specialize std::hash::operator() for user-defined type in unordered containers?
To support user-defined key types in std::unordered_set<Key> and std::unordered_map<Key, Value>
one has to provide operator==(Key, Key) and a hash functor:
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What is the difference between Lisp-1 and Lisp-2?
I have tried to understand the difference between Lisp-1 and Lisp-2 and how this relates to Clojure but I still do not understand properly. Can anyone enlighten me?
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Nullable type issue with ?: Conditional Operator
...looking at the variable to which it is assigned, but by looking at the operands instead. It finds <null> and DateTime and instead of finding the common ancestor type, it just tries to find a conversion between each other. (Extra bit: C# recognizes a <null> type, i.e. the type of every nu...
Match whole string
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Use the start and end delimiters: ^abc$
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