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A std::map that keep track of the order of insertion?

... You might combine a std::vector with a std::tr1::unordered_map (a hash table). Here's a link to Boost's documentation for unordered_map. You can use the vector to keep track of the insertion order and the hash table to do the frequent lookups. If you're doing hundreds of thousands of lookups,...
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What is the difference between a map and a dictionary?

... languages use still other terms ("Object" in Javascript, "Hash" in Ruby, "Table" in Lua), but those all have separate meanings in programming too, so I'd avoid them. See here for more info. share | ...
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Can I use a function for a default value in MySql?

...ntheses to distinguish them from literal constant default values. CREATE TABLE t1 ( uuid_field VARCHAR(32) DEFAULT (uuid()), binary_uuid BINARY(16) DEFAULT (UUID_TO_BIN(UUID())) ); share | ...
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SQL Update with row_number()

... attempt failed primarily because you named the CTE same as the underlying table and made the CTE look as if it was a recursive CTE, because it essentially referenced itself. A recursive CTE must have a specific structure which requires the use of the UNION ALL set operator. Instead, you could just...
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Are foreign keys really necessary in a database design?

... code using things like ON DELETE CASCADE. This means that if you have one table containing users and another containing orders or something, then deleting a user could automatically delete all orders that point to that user. ...
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What is the use of the @Temporal annotation in Hibernate?

...on and you want to store precise date/time or both (TIMESTAMP) in database table. The temporal precision is not specified in core Java APIs. @Temporal is a JPA annotation that converts back and forth between timestamp and java.util.Date. It also converts time-stamp into time. For example, in the s...
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How does C compute sin() and other math functions?

...ximations for both sin(x) and cos(x), then using values from a precomputed table to refine the approximation. When |x| > 2, none of the above algorithms would work, so the code starts by computing some value closer to 0 that can be fed to sin or cos instead. There's yet another branch to deal wit...
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Laravel Eloquent ORM Transactions

...ging this. After reading THIS stackoverflow answer, I realized my database tables were using MyISAM instead of InnoDB. For transactions to work on Laravel (or anywhere else as it seems), it is required that your tables are set to use InnoDB Why? Quoting MySQL Transactions and Atomic Operations docs ...
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How to have comments in IntelliSense for function in Visual Studio?

...customize your <include> use. <list type="bullet" | "number" | "table"> <listheader> <term>term</term> <description>description</description> </listheader> <item> <term>term</term> <des...
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Better way to set distance between flexbox items

...llapsing margins. Flexbox doesn't have anything akin to border-spacing for tables (except for CSS property gap which isn't supported in Safari, caniuse) Therefore achieving what you are asking for is a bit more difficult. In my experience, the "cleanest" way that doesn't use :first-child/:last-chil...