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“Insert if not exists” statement in SQLite
I have an SQLite database. I am trying to insert values ( users_id , lessoninfo_id ) in table bookmarks , only if both do not exist before in a row.
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dplyr: “Error in n(): function should not be called directly”
I am attempting to reproduce one of the examples in the dplyr package but am getting this error message. I am expecting to see a new column n produced with the frequency of each combination. What am I missing? I triple checked that the package is loaded.
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Simulate airplane mode in iPhone Simulator
Is there any way to simulate airplane mode in the iPhone Simulator?
4 Answers
4
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Overwrite or override
It might seem to be a stupid question but I'm just so curious and want to use the correct term when talking about the issue. Couldn't find a similar question here so I decided to create a new one.
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Deprecated warning for Rails 4 has_many with order
...and needs to be replaced with lambda scope block as shown in the warning you've posted in the question. Another point to note is that this scope block needs to be passed before any other association options such as dependent: :destroy etc.
Give this a try:
has_many :contents, -> { order(:po...
Webstorm: “Cannot Resolve Directory”
This is starting to bug me and I'd either like it turned off or fixed. So Webstorm has a sweet feature in it's HTML parser that will attempt to resolve directories in strings that are supposed to reference a file in your project. For example:
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Fetch first element which matches criteria
...to get first element that matches a criteria in a stream? I've tried this but doesn't work
3 Answers
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Can I tell the Chrome script debugger to ignore jquery.js?
Is there a way to tell the Chrome debugger (or maybe Firebug?) to not break within certain files? To assume they're not broken, essentially? This seems like something they might build in.
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Git: How to reuse/retain commit messages after 'git reset'?
As Git user I regular come across the situation, that I need to rework one or more commits in a way which do not fit into --amend or rebase -i with fixup commits. Typically I would do something like
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Use of an exclamation mark in a Git commit message via the command line
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Use single quotes instead of double quotes
git commit -am 'Nailed it!'
Alternatively, if you need to use double quotes for whatever reason but still want a literal ! then turn off history expansion at the top of your scrip...