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How to replace strings containing slashes with sed?
... to use a different delimiter in your search/replace lines, e.g.:
s:?page=one&:pageone:g
You can use any character as a delimiter that's not part of either string. Or, you could escape it with a backslash:
s/\//foo/
Which would replace / with foo. You'd want to use the escaped backslash in...
Postgres: Distinct but only for one column
...
To do a distinct on only one (or n) column(s):
select distinct on (name)
name, col1, col2
from names
This will return any of the rows containing the name. If you want to control which of the rows will be returned you need to order:
select distin...
Java 8: Where is TriFunction (and kin) in java.util.function? Or what is the alternative?
...ructive function, as the name implies, constructs something, a destructive one destroys something, but not in the way you may think now.
For example, the function
Function<Integer,Integer> f = (x,y) -> x + y
is a constructive one.
As you need to construct something. In the example
y...
Index all *except* one item in python
...port numpy as np
>>> arr = np.arange(1,10)
>>> mask = np.ones(arr.shape,dtype=bool)
>>> mask[5]=0
>>> arr[mask]
array([1, 2, 3, 4, 5, 7, 8, 9])
Something similar can be achieved using itertools without numpy
>>> from itertools import compress
>>&...
Understanding recursion [closed]
...e containing five flowers?
Answer: if the vase is not empty, you take out one flower
and then you empty a vase containing four flowers.
How do you empty a vase containing four flowers?
Answer: if the vase is not empty, you take out one flower
and then you empty a vase containing three flowers.
...
How can I pair socks from a pile efficiently?
...as doing it is not very efficient. I was doing a naive search — picking one sock and "iterating" the pile in order to find its pair. This requires iterating over n/2 * n/4 = n 2 /8 socks on average.
...
What are the differences between a clustered and a non-clustered index?
...
Clustered Index
Only one per table
Faster to read than non clustered as data is physically stored in index order
Non Clustered Index
Can be used many times per table
Quicker for insert and update operations than a clustered index
Both types...
INNER JOIN vs LEFT JOIN performance in SQL Server
...alent to an INNER JOIN, so you cannot simply go replacing all instances of one with the other!)
Most likely your performance problems lie elsewhere, such as not having a candidate key or foreign key indexed properly. 9 tables is quite a lot to be joining so the slowdown could literally be almost a...
Python's many ways of string formatting — are the older ones (going to be) deprecated?
...ocs intended to explicitly emphasise that it will not be deprecated, let alone removed. The docs remain opinionated on the relative merits of different kinds of string formatting, but they're also clear the %-formatting isn't going to get deprecated or removed.
What's more, the most recent change t...
Difference between method and function in Scala
...ns (6.23) and Method Values (6.7). Curiously, function values is spoken of one time on 3.2.9, and no where else.
A Function Type is (roughly) a type of the form (T1, ..., Tn) => U, which is a shorthand for the trait FunctionN in the standard library. Anonymous Functions and Method Values have fu...