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UPDATE multiple tables in MySQL using LEFT JOIN
...d table.
UPDATE t1
LEFT JOIN
t2
ON
t2.some_id = t1.some_id
LEFT JOIN
t3
ON
t2.t3_id = t3.id
SET
t1.new_column = t3.column;
This would be useful in a case where you had users and groups, and you wanted a user to be able to add their own variation of the group name, so originally you would...
subtract two times in python
...
t1 = timedelta(hours=7, minutes=36)
t2 = timedelta(hours=11, minutes=32)
t3 = timedelta(hours=13, minutes=7)
t4 = timedelta(hours=21, minutes=0)
arrival = t2 - t1
lunch = (t3 - t2 - timedelta(hours=1))
departure = t4 - t3
print(arrival, lunch, departure)
...
Insert multiple rows WITHOUT repeating the “INSERT INTO …” part of the statement?
...T INTO table1 (column2, column3)
SELECT
t2.column,
t3.column
FROM table2 t2
INNER JOIN table3 t3
ON t2.ID = t3.ID
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...
What is the best algorithm for overriding GetHashCode?
...HashCode();
}
}
public static int GetHashCode<T1, T2, T3>(T1 arg1, T2 arg2, T3 arg3)
{
unchecked
{
int hash = arg1.GetHashCode();
hash = 31 * hash + arg2.GetHashCode();
return 31 * hash + arg3.GetHashCode();
}
...
What's the best way to join on the same table twice?
... t.PhoneNumber3
t1.SomeOtherFieldForPhone1, t2.someOtherFieldForPhone2, t3.someOtherFieldForPhone3
FROM
(
(
Table1 AS t LEFT JOIN Table2 AS t3 ON t.PhoneNumber3 = t3.PhoneNumber
)
LEFT JOIN Table2 AS t2 ON t.PhoneNumber2 = t2.PhoneNumber
)
LEFT JOIN Table2 AS t1 ON t.PhoneNumber1 = t1.Phone...
React.js: Identifying different inputs with one onChange handler
...e some kind of delay in the state object updating.
– T3db0t
Jan 11 '14 at 3:47
1
The "kind of del...
In Scala how do I remove duplicates from a list?
...nSortedMut1: 4399.7055ms
distinctOnSortedMut2: 246.099ms
distinctOnSortedMut3: 344.0758ms
distinctOnSortedMut4: 247.0685ms
List size 1e7, random 0 to 100
------------------------------
distinct : 88.9158ms
distinctOnSorted : 41.0373ms
distinctOnSortedMut1: 3283.8945ms
distinctOnSorted...
Why must jUnit's fixtureSetup be static?
... System.out.println(this + "\ttest2");
}
@Test
public void test3() {
System.out.println(this + "\ttest3");
}
}
Which prints:
beforeClass
ExampleTest@3358fd70 before
ExampleTest@3358fd70 test1
ExampleTest@3358fd70 after
ExampleTest@6293068a before
ExampleTest@6...
How to create a MySQL hierarchical recursive query
...,
p4.parent_id as parent4_id,
p3.parent_id as parent3_id,
p2.parent_id as parent2_id,
p1.parent_id as parent_id,
p1.id as product_id,
p1.name
from products p1
left join products p2 on p2.id = p1.parent_id
left join p...
Convert timedelta to total seconds
...>> t1 = time.gmtime()
>>> t2 = time.mktime(t1)
>>> t3 = datetime.datetime.fromtimestamp(t2)
>>> print t0
1301735358.78
>>> print t1
time.struct_time(tm_year=2011, tm_mon=4, tm_mday=2, tm_hour=9, tm_min=31, tm_sec=3, tm_wday=5, tm_yday=92, tm_isdst=0) ### thi...