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Reference alias (calculated in SELECT) in WHERE clause
The calculated value BalanceDue that is set as a variable in the list of selected columns cannot be used in the WHERE clause.
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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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PostgreSQL - fetch the row which has the Max value for a column
...sted index lookup into lives - on my machine
-- the latter query plan was selected given my memory settings and
-- histogram
SELECT
l1.*
FROM
lives AS l1
INNER JOIN (
SELECT
usr_id,
MAX(time_stamp) AS time_stamp_max
FROM
lives
GROUP BY
usr_id
) AS l2
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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 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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Can a class member function template be virtual?
...ember functions are resolved statically. That is, the
member function is selected statically (at compile-time) based on the
type of the pointer (or reference) to the object.
In contrast, virtual member functions are resolved dynamically (at
run-time). That is, the member function is selec...
Linq code to select one item
I find myself writing a lot of code like this to select one item that matches
7 Answers
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How did I get a value larger than 8 bits in size from an 8-bit integer?
...s extended to bit-width sizeof(int) . As I understand it, incrementing a char shouldn't ever be undefined behavior as long as sizeof(char) < sizeof(int) . But that doesn't explain how c is getting an impossible value. As an 8-bit integer, how can c hold values greater than its bit-width...
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...
How can I capitalize the first letter of each word in a string?
... If the optional second argument sep is absent or None, runs of whitespace characters are replaced by a single space and leading and trailing whitespace are removed, otherwise sep is used to split and join the words.
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