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Java String array: is there a size of method?
I come from a php background and in php, there is an array_size() function which tells you how many elements in the array are used.
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How do I create a unique constraint that also allows nulls?
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SQL Server 2008 +
You can create a unique index that accept multiple NULLs with a WHERE clause. See the answer below.
Prior to SQL Server 2008
You cannot create a UNIQUE constraint and allow NULLs. You need set a default value of NEWID().
Update the existing valu...
How do I replace a character at a particular index in JavaScript?
I have a string, let's say Hello world and I need to replace the char at index 3. How can I replace a char by specifying a index?
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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, ...
Prefer composition over inheritance?
...ifference, it's easier to explain.
Procedural Code
An example of this is PHP without the use of classes (particularly before PHP5). All logic is encoded in a set of functions. You may include other files containing helper functions and so on and conduct your business logic by passing data around i...