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ActiveRecord: size vs count
In Rails, you can find the number of records using both Model.size and Model.count . If you're dealing with more complex queries is there any advantage to using one method over the other? How are they different?
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How do you run multiple programs in parallel from a bash script?
...t prog1.
Send it to background, but keep printing its output.
Start prog2, and keep it in foreground, so you can close it with ctrl-c.
When you close prog2, you'll return to prog1's foreground, so you can also close it with ctrl-c.
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Rails migrations: self.up and self.down versus change
Looks like the new rails version has "change" versus self.up and self.down methods.
3 Answers
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How to search through all Git and Mercurial commits in the repository for a certain string?
I have a Git repository with few branches and dangling commits. I would like to search all such commits in repository for a specific string.
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Rails I18n validation deprecation warning
I just updated to rails 4.0.2 and I'm getting this warning:
5 Answers
5
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How should equals and hashcode be implemented when using JPA and Hibernate
How should model class's equals and hashcode be implemented in Hibernate? What are the common pitfalls? Is the default implementation good enough for most cases? Is there any sense to use business keys?
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How do I concatenate const/literal strings in C?
I'm working in C, and I have to concatenate a few things.
17 Answers
17
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Multiple DB Contexts in the Same DB and Application in EF 6 and Code First Migrations
...t uses EF 6. I am using Code First Migrations. I am using Areas in the app and would like to have different DbContexts in each area to break it up. I know EF 6 has ContextKey, but I can't find complete information on how to use it. Currently I can only use migrations one context at a time.
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“unrecognized import path” with go get
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Just installed fresh golang 1.3 on fedora 20 and go get gives the same error. GOROOT is set to /usr, go itself installed into /usr, not /usr/local. Set GOPATH to $HOME/go. Any idea what else to check ?
– Dfr
Dec 2 '14 at 15:45
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When to use inline function and when not to use it?
I know that inline is a hint or request to compiler and its used to avoid function call overheads.
14 Answers
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