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How do I overload the square-bracket operator in C#?
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This isn't operator overloading. It is indexer
– Destructor
May 12 '16 at 8:32
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How to select rows that have current day's timestamp?
...table` WHERE DATE(`timestamp`) = CURDATE()
I guess using DATE still uses INDEX.
see the execution plan on the DEMO
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How to set iPhone UIView z index?
I want to move one view on top of another, how can I know the z index of the view, and how to move on to top?
9 Answers
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Pros and Cons of Interface constants [closed]
PHP interfaces allow the definition of constants in an interface, e.g.
2 Answers
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Difference between single quotes and double quotes in Javascript [duplicate]
I know that in PHP, the only difference between double quotes and single quotes is the interpretation of variable inside a string and the treatment of escape characters.
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Shortcut to comment out a block of code with sublime text
...nt with
Ctrl+Shift+/
Source: http://www.sublimetext.com/forum/viewtopic.php?f=3&t=2967
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How can you determine how much disk space a particular MySQL table is taking up?
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For a table mydb.mytable run this for:
BYTES
SELECT (data_length+index_length) tablesize
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';
KILOBYTES
SELECT (data_length+index_length)/power(1024,1) tablesize_kb
FROM information_schema.tables
WHERE table_s...
B-Tree vs Hash Table
In MySQL, an index type is a b-tree, and access an element in a b-tree is in logarithmic amortized time O(log(n)) .
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Creating a Pandas DataFrame from a Numpy array: How do I specify the index column and column headers
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You need to specify data, index and columns to DataFrame constructor, as in:
>>> pd.DataFrame(data=data[1:,1:], # values
... index=data[1:,0], # 1st column as index
... columns=data[0,1:]) # 1st row as the co...
When and why are database joins expensive?
... working set. Joins involving properly selected keys with correctly set up indexes are cheap, not expensive, because they allow significant pruning of the result before the rows are materialised.
Materialising the result involves bulk disk reads which are the most expensive aspect of the exercise ...