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Nullable Foreign Key bad practice?
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Using NULL would be a good way to clean up incomplete orders:
SELECT * FROM `orders`
WHERE `started_time` < (UNIX_TIMESTAMP() + 900) AND `customer_id` IS NULL
The above would show orders older than 15 minutes without a related customer ID.
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Does JavaScript guarantee object property order?
...ruenbaum Your comment is false. In ES2015 the order is guaranteed only for selected methods. See answer of ftor below.
– Piotr Dobrogost
Oct 7 '16 at 15:34
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Non greedy (reluctant) regex matching in sed?
...nswering your question
Using approach #2 (delimited expression) you should select two appropriate expressions:
EDE: [^:/]\/
SDE: http:
Usage:
$ sed 's/\([^:/]\/\).*/\1/g; s/\(\(http:.*\)*.\)*/\1/' <<< 'http://www.suepearson.co.uk/product/174/71/3816/'
Output:
http://www.suepearson.co.u...
Renaming a virtualenv folder without breaking it
...ate_this.py instead of using the
location of the Python interpreter to
select the environment.
Note: you must run this after you've
installed any packages into the
environment. If you make an
environment relocatable, then install
a new package, you must run virtualenv
--relocatabl...
What is a clean, pythonic way to have multiple constructors in Python?
...sing __new__.
This could be used if the type of initialization cannot be selected based on the type of the constructor argument, and the constructors do not share code.
Example:
class MyClass(set):
def __init__(self, filename):
self._value = load_from_file(filename)
@classmeth...
Do I need to disable NSLog before release Application?
...s is through 'edit scheme' -> 'run app name' -> under the tab 'info' select using the drop-down box between debug & release. In the release version you won't see any NSLog output in the debug console !
How does this all work?
first of all, one must know that a preprocessor is relatively ...
Remove columns from DataTable in C#
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Aside from limiting the columns selected to reduce bandwidth and memory:
DataTable t;
t.Columns.Remove("columnName");
t.Columns.RemoveAt(columnIndex);
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Edit and Continue: “Changes are not allowed when…”
...o edit it.
(vs2017) Go to Tools > Options > Debugging and uncheck (deselect) 'Edit and Continue'. This is actually the opposite of the 'conventional' advice (see some other points in this post). It does not allow you to actually make changes in your running program (i.e. it does not hot-swap t...
LEN function not including trailing spaces in SQL Server
..."returns the number of bytes used to represent any expression".
Example:
SELECT
ID,
TestField,
LEN(TestField) As LenOfTestField, -- Does not include trailing spaces
DATALENGTH(TestField) As DataLengthOfTestField -- Shows the true length of data, including trailing...
optional parameters in SQL Server stored proc?
...rameter*/
INSERT INTO ........
END
/* and use it in the query as so*/
SELECT *
FROM Table
WHERE Column = @Parameter
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