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How can I see the specific value of the sql_mode?
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| @@sql_mode |
+------------+
| |
+------------+
1 row in set (0.00 sec)
mysql> set sql_mode=ORACLE;
Query OK, 0 rows affected (0.00 sec)
mysql> SELECT @@sql_mode;
+-------------------------------------------------------------------------------------------------------------------...
Why does substring slicing with index out of range work?
...s. Look what happens when you do the same thing to a list:
>>> [0, 1, 2, 3, 4, 5][3]
3
>>> [0, 1, 2, 3, 4, 5][3:4]
[3]
Here the difference is obvious. In the case of strings, the results appear to be identical because in Python, there's no such thing as an individual character ...
How can I create a UIColor from a hex string?
How can I create a UIColor from a hexadecimal string format, such as #00FF00 ?
47 Answers
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The cast to value type 'Int32' failed because the materialized value is null
...where there can be unexpected nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more general approach is to use ?? which will be translated to COALESCE whenever there is a r...
Add leading zeroes to number in Java? [duplicate]
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1330
String.format (https://docs.oracle.com/javase/1.5.0/docs/api/java/util/Formatter.html#syntax)
I...
Move an item inside a list?
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answered Jul 3 '10 at 23:15
David ZDavid Z
111k2323 gold badges218218 silver badges256256 bronze badges
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Is it possible to modify variable in python that is in outer, but not global, scope?
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100
Python 3.x has the nonlocal keyword. I think this does what you want, but I'm not sure if you ...
Using CSS how to change only the 2nd column of a table
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answered Mar 29 '10 at 0:04
Nick Craver♦Nick Craver
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Pandas aggregate count distinct
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How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "user_id...
Using {} in a case statement. Why?
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Macke
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answered Nov 17 '13 at 13:25
RotemRotem
19.2k66 gold badge...