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Best ways to teach a beginner to program? [closed]
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edited Apr 7 '09 at 13:34
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Why does CSS not support negative padding?
...gives me a satisfactory reason. Cheers. :)
– ikartik90
Feb 12 '11 at 6:29
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What if you want to ...
How to stretch the background image to fill a div
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How to pass all arguments passed to my bash script to a function of mine? [duplicate]
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The $@ variable expands to all command-line parameters separated by spaces. Here is an exampl...
Removing multiple files from a Git repo that have already been deleted from disk
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For Git 1.x
$ git add -u
This tells git to automatically stage tracked files -- including del...
Simultaneously merge multiple data.frames in a list
....frame(i = c("c","d","a"), l = 7:9, stringsAsFactors=FALSE)
Update June 2018: I divided the answer in three sections representing three different ways to perform the merge. You probably want to use the purrr way if you are already using the tidyverse packages. For comparison purposes below, you'll...
insert a NOT NULL column to an existing table
...lue for your column:
ALTER TABLE MY_TABLE ADD STAGE INT NOT NULL DEFAULT '0'
UPD: Please note that answer above contains GO which is a must when you run this code on Microsoft SQL server. If you want to perform the same operation on Oracle or MySQL you need to use semicolon ; like that:
ALTER ...
Show/hide 'div' using JavaScript
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How to show or hide an element:
In order to show or hide an element, manipulate the element's s...
Is it good practice to NULL a pointer after deleting it?
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Setting a pointer to 0 (which is "null" in standard C++, the NULL define from C is somewhat different) avoids crashes on double deletes.
Consider the following:
Foo* foo = 0; // Sets the pointer to 0 (C++ NULL)
delete foo; // Won't do anything
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Can you have if-then-else logic in SQL? [duplicate]
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You can make the following sql query
IF ((SELECT COUNT(*) FROM table1 WHERE project = 1) > ...