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What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
...noDB engine. In that case you would have to drop the foreign key, and then do the alter table and drop the column.
But the tricky part is that you can't drop the foreign key using the column name, but instead you would have to find the name used to index it. To find that, issue the following select...
Get the cartesian product of a series of lists?
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What is the use of * before somelists? What does it do?
– Vineet Kumar Doshi
Aug 25 '15 at 9:04
7
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Insert all values of a table into another table in SQL
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The insert statement actually has a syntax for doing just that. It's a lot easier if you specify the column names rather than selecting "*" though:
INSERT INTO new_table (Foo, Bar, Fizz, Buzz)
SELECT Foo, Bar, Fizz, Buzz
FROM initial_table
-- optionally WHERE ...
I'd b...
Age from birthdate in python
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That can be done much simpler considering that int(True) is 1 and int(False) is 0:
from datetime import date
def calculate_age(born):
today = date.today()
return today.year - born.year - ((today.month, today.day) < (born.mon...
If statement in aspx page
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if the purpose is to show or hide a part of the page then you can do the following things
1) wrap it in markup with
<% if(somecondition) { %>
some html
<% } %>
2) Wrap the parts in a Panel control and in codebehind use the if statement to set the Visible property of the ...
How can I declare and define multiple variables in one line using C++?
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int column, row, index = 0;
Only index is set to zero.
However you can do the following:
int column, row, index;
column = index = row = 0;
But personally I prefer the following which has been pointed out.
It's a more readable form in my view.
int column = 0, row = 0, index = 0;
or
int col...
Get mouse wheel events in jQuery?
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There's a plugin that detects up/down mouse wheel and velocity over a region.
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Casting to string in JavaScript
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They do behave differently when the value is null.
null.toString() throws an error - Cannot call method 'toString' of null
String(null) returns - "null"
null + "" also returns - "null"
Very similar behaviour happens if value i...
iOS 7 - Failing to instantiate default view controller
... I go for the run button e click on it, then the project gets built but it does not show in the iOS Simulator and I get the following message:
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Definition of “downstream” and “upstream”
...ve started playing with Git and have come across the terms "upstream" and "downstream". I've seen these before but never understood them fully. What do these terms mean in the context of SCMs ( Software Configuration Management tools) and source code?
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