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What are the advantages of using a schema-free database like MongoDB compared to a relational databa
I'm used to using relational databases like MySQL or PostgreSQL, and combined with MVC frameworks such as Symfony, RoR or Django, and I think it works great.
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Find size of an array in Perl
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The first and third ways are the same: they evaluate an array in scalar context. I would consider this to be the standard way to get an array's size.
The second way actually returns the last index of the array, which is not (usually) ...
Invoking JavaScript code in an iframe from the parent page
Basically, I have an iframe embedded in a page and the iframe has some JavaScript routines I need to invoke from the parent page.
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mysql Foreign key constraint is incorrectly formed error
I have two tables, table1 is the parent table with a column ID and table2 with a column IDFromTable1 (not the actual name) when I put a FK on IDFromTable1 to ID in table1 I get the error Foreign key constraint is incorrectly formed error . I would like to delete table 2 record if tab...
The model backing the context has changed since the database was created
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I've changed my production db manually and turned off the migration and it works, Thanks
– Mohsen Afshin
Sep 10 '12 at 21:05
13
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How do I use vim registers?
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Registers in Vim let you run actions or commands on text stored within them. To access a register, you type "a before a command, where a is the name of a register. If you want to copy the current line into register k, you can type
"kyy
Or you can append to a regis...
What integer hash function are good that accepts an integer hash key?
... a multiplier that is in the order of your hash size (2^32 in the example) and has no common factors with it. This way the hash function covers all your hash space uniformly.
Edit: The biggest disadvantage of this hash function is that it preserves divisibility, so if your integers are all divisibl...
IntelliJ inspection gives “Cannot resolve symbol” but still compiles code
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First of all you should try File | Invalidate Caches and if it doesn't help, delete IDEA system directory. Then re-import the Maven project and see if it helps.
In some weird cases compiled classes may report wrong info and confuse IDEA. Verify that the classes from this jar r...
How do I fix blurry text in my HTML5 canvas?
I am a total n00b with HTML5 and am working with the canvas to render shapes, colors, and text. In my app, I have a view adapter that creates a canvas dynamically, and fills it with content. This works really nicely, except that my text is rendered very fuzzy/blurry/stretched. I have seen a ...
When do I need to use a semicolon vs a slash in Oracle SQL?
...nits" of work (creating a PL/SQL object, running a PL/SQL anonymous block, and executing a DML statement) can be picked out more easily by eye.
Also, if you eventually move to something like Ant for deployment it will simplify the definition of targets to have a consistent statement delimiter.
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