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What is the fastest way to create a checksum for large files in C#
...ming a one-to-one comparison. Unfortunately, I'm using the MD5 hash as an index to look for unique files among many duplicates (many-to-many checks).
– Nathan Goings
Aug 23 '18 at 20:15
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How to delete or add column in SQLITE?
...upports a limited subset of ALTER TABLE. The ALTER TABLE command in SQLite allows the user to rename a table or to add a new column to an existing table. It is not possible to rename a column, remove a column, or add or remove constraints from a table.
You can:
create new table as the one you ar...
Python: avoid new line with print command [duplicate]
...ork on 3.x, you suppress using print('whateverhere', end='') where end normally defaults to '\n'
– Jon Clements♦
Jun 29 '12 at 17:19
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How to check iOS version?
...system version as an indication of device or OS capabilities. There is usually a more reliable method of checking whether a particular feature or class is available.
Checking for the presence of APIs:
For example, you can check if UIPopoverController is available on the current device using NSCla...
How to make a variadic macro (variable number of arguments)
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The reason for ## before VA_ARGS is that it swallows the preceding comma in case the variable-argument list is empty, eg. FOO("a") expands to printf("a"). This is an extension of gcc (and vc++, maybe), C99 requires at least one argument to be present in place of the elli...
Why does calling a function in the Node.js REPL with )( work?
Why is it possible to call function in JavaScript like this, tested with node.js:
3 Answers
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What is the definition of “interface” in object oriented programming
... one of the more overloaded and confusing terms in development.
It is actually a concept of abstraction and encapsulation. For a given "box", it declares the "inputs" and "outputs" of that box. In the world of software, that usually means the operations that can be invoked on the box (along with ar...
How to limit the maximum value of a numeric field in a Django model?
...ormer can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a certain range, e.g. 0.0-5.0 ?
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Space between two rows in a table?
...for people using screen-readers or other assistant devices, as well as for indexing purposes and the likes. It might not make a huge difference but it is good to keep it back in your head when developing a website :)
– Justus Romijn
Feb 7 '18 at 11:46
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Efficiently convert rows to columns in sql server
...d than just a single script but gives you much more flexibility.
First of all There are 3 objects:
User defined TABLE type [ColumnActionList] -> holds data as
parameter
SP [proc_PivotPrepare] -> prepares our data
SP [proc_PivotExecute] -> execute the script
CREATE TYPE [dbo].[ColumnAc...