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Insert multiple rows WITHOUT repeating the “INSERT INTO …” part of the statement?
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What happens, if one value set is faulty? Will all inserts rolled back or just the faulty row?
– netblognet
Feb 8 '16 at 7:26
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Change from SQLite to PostgreSQL in a fresh Rails project
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You can name it whatever you want. If your project name is 'calculator' I would name them calculator_production, calculator_test, calculator_development
– Chris Barretto
Jul 24 '11 at 17:28
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Rails migration: t.references with alternative name?
... about not being able to add foreign_key: true to the references lines was what was tripping me up. Adding the add_foreign_key and specifying the column name for those did the trick.
– Matthew Clark
Sep 16 '15 at 16:22
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Google Maps: how to get country, state/province/region, city given a lat/long value?
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What you are looking for is called reverse geocoding. Google provides a server-side reverse geocoding service through the Google Geocoding API, which you should be able to use for your project.
This is how a response to the ...
Unable to create/open lock file: /data/mongod.lock errno:13 Permission denied
...enied'.
First I ran sudo service mongodb stop.
Then I used ls -la to see what group & owner mongodb assigned to /var/lib/mongodb (existing path) and I changed the /data/db (new path) with chown and chgrp to match. (example: sudo chown -R mongodb:mongodb /data/db)
Then I updated the path in etc...
How do I clone a subdirectory only of a Git repository?
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What you are trying to do is called a sparse checkout, and that feature was added in git 1.7.0 (Feb. 2012). The steps to do a sparse clone are as follows:
mkdir <repo>
cd <repo>
git init
git remote add -f origin ...
Difference between Hashing a Password and Encrypting it
...ou cannot get the original string back. The most you can do is to generate what's called "a collision", that is, finding a different string that provides the same hash. Cryptographically secure hash algorithms are designed to prevent the occurrence of collisions. You can attack a secure hash by the ...
Get a specific bit from byte
...Bit-shifting, to produce the number we want to compare against, is exactly what it sounds like: take the number, represented as a set of bits, and shift those bits left or right by a certain number of places. Because these are binary numbers and so each bit is one greater power-of-two than the one t...
Difference between a Structure and a Union
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struct bar y;
y.a = 3; // OK
y.b = 'c'; // OK
edit: If you're wondering what setting x.b to 'c' changes the value of x.a to, technically speaking it's undefined. On most modern machines a char is 1 byte and an int is 4 bytes, so giving x.b the value 'c' also gives the first byte of x.a that same ...
Comparing two java.util.Dates to see if they are in the same day
...ive to the time zone used by the computer it is running on. If this is not what you need, you have to pass the relevant time zone(s) to the Calendar.getInstance() calls, after you have decided what exactly you mean with "the same day".
And yes, Joda Time's LocalDate would make the whole thing much ...