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SQL query return data from multiple tables
...we need and use a join that correctly identifies what columns to join on.
ERROR 1052 (23000): Column 'ID' in field list is ambiguous
Oh noes! An error in our first query! Yes, and it is a plum. You see, the query has indeed got the right columns, but some of them exist in both tables, so the data...
What is the meaning of “__attribute__((packed, aligned(4))) ”
...gned(1))) sSampleStruct;
so the above specified gcc attribute does not allow the structure padding. so the size will be 8 bytes.
If you wish to do the same for all the structures, simply we can push the alignment value to stack using #pragma
#pragma pack(push, 1)
//Structure 1
......
//Stru...
How to change Rails 3 server default port in develoment?
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First - do not edit anything in your gem path! It will influence all projects, and you will have a lot problems later...
In your project edit script/rails this way:
#!/usr/bin/env ruby
# This command will automatically be run when you run "rails" with Rails 3 gems installed from the root...
How do you query for “is not null” in Mongo?
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This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...
Difference between \b and \B in regex
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\b is a zero-width word boundary. Specifically:
Matches at the position between a word character (anything matched by \w) and a non-word character (anything matched by [^\w] or \W) as well as at the start and/or end of the string if the first and/or last characte...
Determine .NET Framework version for dll
...wing reflector, it will probably complain, and give it a nice non-descript error icon.
– leppie
Aug 11 '10 at 17:15
@l...
What is the difference between ManualResetEvent and AutoResetEvent in .NET?
...or. The ManualResetEvent is the door, which needs to be closed (reset) manually. The AutoResetEvent is a tollbooth, allowing one car to go by and automatically closing before the next one can get through.
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How to get a substring of text?
I have text with length ~700. How do I get only ~30 of its first characters?
5 Answers
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What is the difference between require_relative and require in Ruby?
... the docs:
require_relative complements the builtin method require by allowing you to load a file that is relative to the file containing the require_relative statement.
For example, if you have unit test classes in the "test" directory, and data for them under the test "test/data" directo...
Difference between @import and link in CSS
...se it seems MSIE9 issues two incorrect requests to the server, getting 404 errors I could do without:
[ip] - - [21/Dec/2019:05:49:28 +0000] "GET /screen.css HTTP/1.1" 200 2592 "https://ssb22.user.srcf.net/zhimo/"; "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)" ssb22...