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Rails select helper - Default selected value, how?
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This should do it:
<%= f.select :project_id, @project_select, :selected => params[:pid] %>
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Rails 3: Get Random Record
...You can use the following trick on an indexed column (PostgreSQL syntax):
select *
from my_table
where id >= trunc(
random() * (select max(id) from my_table) + 1
)
order by id
limit 1;
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How do I get extra data from intent on Android?
...TRING);
getArguments().getBoolean(ARG_SECTION_BOOL);
getArguments().getChar(ARG_SECTION_CHAR);
getArguments().getByte(ARG_SECTION_DATA);
}
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How to copy a row and insert in same table with a autoincrement field in MySQL?
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Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSER...
Fastest check if row exists in PostgreSQL
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Use the EXISTS key word for TRUE / FALSE return:
select exists(select 1 from contact where id=12)
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Type erasure techniques
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I would also consider (similar to void*) the use of "raw storage": char buffer[N].
In C++0x you have std::aligned_storage<Size,Align>::type for this.
You can store anything you want in there, as long as it's small enough and you deal with the alignment properly.
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How to select a drop-down menu value with Selenium using Python?
I need to select an element from a drop-down menu.
13 Answers
13
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When should one use a 'www' subdomain?
...nce to its web service?
What would you rather write/type/say.. "www." (4 chars) or "http://" (7 chars) ??
"www." is an established shorthand way of unambiguously communicating the fact that the subject is a web address, not a URL for another network service.
When verbally communicating a web add...
How to find third or nth maximum salary from salary table?
...you want a single) or DENSE_RANK(for all related rows):
WITH CTE AS
(
SELECT EmpID, EmpName, EmpSalary,
RN = ROW_NUMBER() OVER (ORDER BY EmpSalary DESC)
FROM dbo.Salary
)
SELECT EmpID, EmpName, EmpSalary
FROM CTE
WHERE RN = @NthRow
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How to get input type using jquery?
...to now which are checked, and if it is a drop down I need to know which is selected, and I if it is a text/textarea I need to know the values.
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