public/sql.md
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### [1] Why we (I) love relational databases
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* **ACID**
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- * Atomicity (transactions [multiple operations can be "all or nothing"] - even with externalities such as power loss)
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- * Consistency (what's on disk is always acceptable as a state - including constraints, etc.)
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- * Isolation (no transaction affects another)
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+ * Atomicity (if you cluster a number of operations as a "transaction," then they will all be executed or none will be executed - even with externalities such as power loss)
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+ * Consistency (what's on disk is always acceptable - including constraints, etc. In other words, if you unplug the computer that has your database, the database stored on disk will work when the power is restored: The on-disk version will not be corrupted.)
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+ * Isolation (no transaction affects another; so multiple users can all be running their separate transactions and they won't interfere with one another.)
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* Durability (if an insert completes, it is really written to disk)
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* Do we need these?
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* What apps don't need these things?