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DROP IF EXISTS VS DROP?
... syntax is
DROP TABLE IF EXISTS table_name;
The first one will throw an error if the table doesn't exist, or if other database objects depend on it. Most often, the other database objects will be foreign key references, but there may be others, too. (Views, for example.) The second will not th...
What is the iBeacon Bluetooth Profile
...e transmitted BLE advertisement packet looks like this:
d6 be 89 8e 40 24 05 a2 17 6e 3d 71 02 01 1a 1a ff 4c 00 02 15 e2 c5 6d b5 df fb 48 d2 b0 60 d0 f5 a7 10 96 e0 00 00 00 00 c5 52 ab 8d 38 a5
This packet can be broken down as follows:
d6 be 89 8e # Access address for advertising data (this i...
How do I import global modules in Node? I get “Error: Cannot find module ”?
...t seem to import anything modules from my global modules folder. I get the error,
8 Answers
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What is a “batch”, and why is GO used?
...t will rollback all GO's. And if in one GO in the middle You will get some error, and in the end You will do COMMIT, all GO without error will be commited. Is kind of tricky.
– T.Z.
Jun 7 '13 at 7:19
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What is an abstract class in PHP?
...are you?";
}
}
$obj=new AbstractClass();
$obj->printOut();
//Fatal error: Cannot instantiate abstract class AbstractClass
2. Any class that contains at least one abstract method must also be abstract: Abstract class can have abstract and non-abstract methods, but it must contain at least o...
Error when trying vagrant up
I'm using Vagrant for my environment and I've got a little issue:
23 Answers
23
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Practical example where Tuple can be used in .Net 4.0?
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tanasciustanascius
48.8k1515 gold badges105105 silver badges129129 bronze badges
5
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Why isn't String.Empty a constant?
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– Christopher Stevenson
May 17 '13 at 12:05
3
@JeffYates I'd add that the fact that it's not consisten...
C# - What does the Assert() method do? Is it still useful?
...ilation, Assert takes in a Boolean condition as a parameter, and shows the error dialog if the condition is false. The program proceeds without any interruption if the condition is true.
If you compile in Release, all Debug.Assert's are automatically left out.
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Check if value exists in Postgres array
...e_id <@ ANY ('"+employeeIDsArray+"'::int[]) This returns PSQLException: ERROR: missing dimension value
– Ramprasad
Mar 29 '14 at 13:11
3
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