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How can I find which tables reference a given table in Oracle SQL Developer?
...on a table, I can view the constraints, which let me see the foreign keys (and thus which tables are referenced by this table), and I can view the dependencies to see what packages and such reference the table. But I'm not sure how to find which tables reference the table.
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What is the MySQL VARCHAR max size?
...ySQL table has a maximum row size limit of 65,535 bytes, not counting BLOB and TEXT types. BLOB and TEXT columns only contribute 9 to 12 bytes toward the row size limit because their contents are stored separately from the rest of the row. Read more about Limits on Table Column Count and Row Size.
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What are the pros and cons of performing calculations in sql vs. in your application
...ed to access/aggregate a lot of data, doing it at the db server will save bandwidth, and disk io if the aggregates can be done inside indexes)
convenience (sql is not the best language for complex work - especially not great for procedural work, but very good for set-based work; lousy error-handling...
The JPA hashCode() / equals() dilemma
There have been some discussions here about JPA entities and which hashCode() / equals() implementation should be used for JPA entity classes. Most (if not all) of them depend on Hibernate, but I'd like to discuss them JPA-implementation-neutrally (I am using EclipseLink, by the way).
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How to add calendar events in Android?
I'm just getting up to speed on Android, and today in a project meeting someone said that Android has no native calendar app so users just use whatever calendar app they like.
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Excel: last character/string match in a string
... position of a character/string's last occurrence in a string. Search and find both work left-to-right so I can't think how to apply without lengthy recursive algorithm. And this solution now seems obsolete.
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What is the difference between an int and an Integer in Java and C#?
...ut a particular type of programmer knowing the difference between an int and an Integer in Java/C# (Object-Oriented Programming Languages).
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How does a Java HashMap handle different objects with the same hash code?
As per my understanding I think:
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Using a dispatch_once singleton model in Swift
...tl;dr: Use the class constant approach if you are using Swift 1.2 or above and the nested struct approach if you need to support earlier versions.
From my experience with Swift there are three approaches to implement the Singleton pattern that support lazy initialization and thread safety.
Class c...
What does “hashable” mean in Python?
...ue which never changes during its lifetime (it needs a __hash__() method), and can be compared to other objects (it needs an __eq__() or __cmp__() method). Hashable objects which compare equal must have the same hash value.
Hashability makes an object usable as a dictionary key and a set member...