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How To Change DataType of a DataColumn in a DataTable?
... of the column after the DataTable is filled, you can change it after you call FillSchema, but before you call Fill. For example, say the 3rd column is the one you want to convert from double to Int32, you could use:
adapter.FillSchema(table, SchemaType.Source);
table.Columns[2].DataType = typeof (...
Why unsigned integer is not available in PostgreSQL?
I came across this post ( What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL? ) and realized that PostgreSQL does not support unsigned integer.
...
Difference between assertEquals and assertSame in phpunit?
...
I use both sporadically, but according to the docs:
assertSame
Reports an error identified by $message if the two variables $expected and $actual do not have the same type and value."
And as you can see in the example below the above exc...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...ull
IL_0002: stloc.0 // s
IL_0003: ldloc.0 // s
IL_0004: callvirt System.String.get_Length
IL_0009: call System.Console.WriteLine
It is the callvirt opcode that throws the NullReferenceException and it does that when the first argument on the evaluation stack is a null ...
How to fix HTTP 404 on Github Pages?
...
I had just one commit with all my files. I pushed an empty commit, refreshed the page and it worked.
git commit --allow-empty -m "Trigger rebuild"
git push
If this doesn't work, as @Hendrikto pointed out in the comments, check out the Github status ...
html select option separator
...on>First</option>
</optgroup>
<optgroup label="_________">
<option>Second</option>
<option>Third</option>
</optgroup>
</select>
disabled option (a bit better):
<select>
<option>Fir...
How to convert list of tuples to multiple lists?
...
xs, ys = [x for x, y in zs], [y for x, y in zs]
return xs, ys
if __name__ == '__main__':
from timeit import timeit
setup_string='''\
N = 2000000
xs = list(range(1, N))
ys = list(range(N+1, N*2))
zs = list(zip(xs, ys))
from __main__ import t1, t2, t3
'''
print(f'zip:\t\t{timeit(...
postgresql list and order tables by size
How can I list all the tables of a PostgreSQL database and order them by size ?
7 Answers
...
How can I return two values from a function in Python?
... two values, but you can return a tuple or a list and unpack it after the call:
def select_choice():
...
return i, card # or [i, card]
my_i, my_card = select_choice()
On line return i, card i, card means creating a tuple. You can also use parenthesis like return (i, card), but tuples ar...
Git - Undo pushed commits
...lution that keeps no traces of the "undo".
NOTE: don't do this if someone allready pulled your change
(I would use this only on my personal repo)
do:
git reset <previous label or sha1>
this will re-checkout all the updates locally (so git status will list all updated files)
then you "do ...