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What is the difference between String.slice and String.substring?
...l be set to string.length + stop if stop is negative. Remember stop is the index after the last character extracted!
– user1537366
Dec 9 '14 at 15:53
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How do you find the disk size of a Postgres / PostgreSQL table and its indexes
...coming to Postgres from Oracle and looking for a way to find the table and index size in terms of bytes/MB/GB/etc , or even better the size for all tables. In Oracle I had a nasty long query that looked at user_lobs and user_segments to give back an answer.
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Removing Data From ElasticSearch
...ing to figure out how to remove data from ElasticSearch. I have deleted my indexes. However, that doesn't seem to actually remove the data itself. The other stuff I've seen points to the Delete by Query feature. However, I'm not even sure what to query on. I know my indexes. Essentially, I'd like ...
How can I use map and receive an index as well in Scala?
... List/Sequence built-in that behaves like map and provides the element's index as well?
8 Answers
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Data structure: insert, remove, contains, get random element, all at O(1)
... in the array.
insert(value): append the value to array and let i be its index in A. Set H[value]=i.
remove(value): We are going to replace the cell that contains value in A with the last element in A. let d be the last element in the array A at index m. let i be H[value], the index in the array o...
Fast permutation -> number -> permutation mapping algorithms
...d.
a, the first element, ends up at the second position, so we assign it index 1.
b ends up at the fourth position, which would be index 3, but it's the third remaining one, so we assign it 2.
c ends up at the first remaining position, which is always 0.
d ends up at the last remaining position, ...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
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To create these constraints through the GUI you need the "indexes and keys" dialogue not the check constraints one.
But in your case you just need to run the piece of code you already have. It doesn't need to be entered into the expression dialogue at all.
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boost Composite keys - C/C++ - 清泛网 - 专注C/C++及内核技术
...n two or more fields of a given table The analogous concept in Boost MultiIndex is Composite keys
In relational databases, composite keys depend on two or more fields of a given table. The analogous concept in Boost.MultiIndex is modeled by means of composite_key, as shown in the example:
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git update-index --assume-unchanged returns “fatal unable to mark file”
...ng git ls-files -o. However in my case, I also tried executing git update-index --assume-unchanged against a file that was not listed when executing ls-files -o, and I still received the same error "fatal: Unable to mark file".
I thought that perhaps it was a bug, and downloaded the latest version...
Insert an element at a specific index in a list and return the updated list
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l.insert(index, obj) doesn't actually return anything. It just updates the list.
As ATO said, you can do b = a[:index] + [obj] + a[index:].
However, another way is:
a = [1, 2, 4]
b = a[:]
b.insert(2, 3)
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