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Reset the database (purge all), then seed a database
... the whole shebang just to reload your data, you could use MyModel.destroy_all (or delete_all) in the seed.db file to clean out a table before your MyModel.create!(...) statements load the data. Then, you can redo the db:seed operation over and over. (Obviously, this only affects the tables you've...
SQL JOIN and different types of JOINs
... and start with cross join and then "build" inner join on top of it. After all, the mere concept of cross join invalidates these informal and inaccurate Venn diagram visualisations...
– Lukas Eder
Apr 21 '17 at 17:25
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How do I temporarily disable triggers in PostgreSQL?
I'm bulk loading data and can re-calculate all trigger modifications much more cheaply after the fact than on a row-by-row basis.
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Remove all subviews?
... its root view controller, in the viewDidAppear: method I need to remove all subviews.
15 Answers
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INSERT IF NOT EXISTS ELSE UPDATE?
...ement case the statement would set it to NULL and then a fresh ID would be allocated.
This approach can also be used if you want to leave particular field values alone if the row in the replacement case but set the field to NULL in the insert case.
For example, assuming you want to leave Seen alon...
Find and replace strings in vim on multiple lines
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@TayyarR The range covers the lines (vertically, so to speak), while the 'g' flag determines whether only one or all matches within the line (so horizontally) are replaced.
– Ingo Karkat
Feb 15 at 20:58
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get all keys set in memcached
How can I get all the keys set in my memcached instance(s)?
6 Answers
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Removing All Child Views from View
How would I remove all child views from a widget? For example, I have a GridView and I dynamically inflate many other LinearLayouts into it; later in my application I am looking to start fresh with that GridView and clear all of its child Views. How would I do this? TIA.
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WAMP error: Forbidden You don't have permission to access /phpmyadmin/ on this server
I am new to WAMP and I have just installed it today.
33 Answers
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How do I ignore all files in a folder with a Git repository in Sourcetree?
...will make git track the folder (by tracking this file). The * means ignore all files, and the !.gitignore means don't ignore the file itself
– Billy Moon
Mar 12 '12 at 10:36
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