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count(*) vs count(column-name) - which is more correct? [duplicate]
Does it make a difference if you do count(*) vs count(column-name) as in these two examples?
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Calculate distance between two latitude-longitude points? (Haversine formula)
How do I calculate the distance between two points specified by latitude and longitude?
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What is the difference between JSON and Object Literal Notation?
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Also note that JSON is a subset of Object Literal Notation
– Sean Kinsey
May 25 '10 at 14:14
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When should we use Observer and Observable?
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You have a concrete example of a Student and a MessageBoard. The Student registers by adding itself to the list of Observers that want to be notified when a new Message is posted to the MessageBoard. When a Message is added to the MessageBoard, it iter...
Convert a String representation of a Dictionary to a dictionary?
How can I convert the str representation of a dict , such as the following string, into a dict ?
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SQL Server Index Naming Conventions [closed]
Is there some standard way to name indexes for SQL Server? It seems that the primary key index is named PK_ and non-clustered indexes typically start with IX_. Are there any naming conventions beyond that for unique indexes?
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Best way to define error codes/strings in Java?
I am writing a web service in Java, and I am trying to figure out the best way to define error codes and their associated error strings . I need to have a numerical error code and an error string grouped together. Both the error code and error string will be sent to the client accessing the web ser...
What do linkers do?
... -r hello_world.o
which contains;
Relocation section '.rela.text' at offset 0x340 contains 1 entries:
Offset Info Type Sym. Value Sym. Name + Addend
00000000000c 000200000001 R_X86_64_64 0000000000000000 .data + 0
The format of this section is fixed docu...
How to capture no file for fs.readFileSync()?
Within node.js readFile() shows how to capture an error, however there is no comment for the readFileSync() function regarding error handling. As such, if I try to use readFileSync() when there is no file, I get the error Error: ENOENT, no such file or directory .
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How do I implement a callback in PHP?
How are callbacks written in PHP?
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