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What's the difference between session.Merge and session.SaveOrUpdate?

...n, do nothing if another object associated with the session has the same identifier, throw an exception if the object has no identifier property, save() it if the object's identifier has the value assigned to a newly instantiated object, save() it if the object is versioned (by a <v...
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How can I get LINQ to return the object which has the max value for a given property? [duplicate]

...l loop through only once. Item biggest = items.Aggregate((i1,i2) => i1.ID > i2.ID ? i1 : i2); Thanks Nick - Here's the proof class Program { static void Main(string[] args) { IEnumerable<Item> items1 = new List<Item>() { new Item(){ ClientID ...
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Storyboard doesn't contain a view controller with identifier

...using Storyboards. I was having the same issue, but I could not find the "Identifier" field in the inspector. Instead, just set the field named "Storyboard ID" to what you would name the Identifier. This field can be found under the "Show the Identity inspector" tab in the inspector. [Note - comme...
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JPA: How to have one-to-many relation of the same Entity type

... Yes, this is possible. This is a special case of the standard bidirectional @ManyToOne/@OneToMany relationship. It is special because the entity on each end of the relationship is the same. The general case is detailed in Section 2.10.2 of the JPA 2.0 spec. Here's a worked example. F...
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How do I replace NA values with zeros in an R dataframe?

... mutate(myCol1 = if_else(is.na(myCol1), 0, myCol1)) Note: This works per selected column, if we need to do this for all column, see @reidjax's answer using mutate_each. share | improve this answer...
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How should I ethically approach user password storage for later plaintext retrieval?

...sing a dictionary of 7776 words (as Diceware uses) which could be randomly selected for a six word passphrase, the passphrase would have an entropy of 77.4 bits. See the Diceware FAQ for more info. a passphrase with about 77 bits of entropy: "admit prose flare table acute flair" a password with ab...
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Redis key naming conventions?

...s website is stated: Try to stick with a schema. For instance "object-type:id:field" can be a nice idea, like in "user:1000:password". I like to use dots for multi-words fields, like in "comment:1234:reply.to". Are you able to query for just the beginning of the key to return all users? If y...
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If threads share the same PID, how can they be identified?

... The four threads will have the same PID but only when viewed from above. What you (as a user) call a PID is not what the kernel (looking from below) calls a PID. In the kernel, each thread has it's own ID, called a PID (although it would possibly make more sens...
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How do I use su to execute the rest of the bash script as that user?

... I did this - but it still asked me for a password. – Hippyjim Oct 19 '13 at 16:30 ...
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How to link to a named anchor in Multimarkdown?

...er to it on the same page by [link text](#abcd). (This uses name= and not id=, for reasons explained in this answer.) Remote references can use [link text](http://...#abcd) of course. This works like a dream, provided you have control over the source and target texts. The anchor can even appear i...