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Is it possible to roll back CREATE TABLE and ALTER TABLE statements in major SQL databases?
...cle Database 11g Release 2 and above - by default, no, but an alternative called edition-based redefinition exists
Older versions of Oracle - no; DDL causes an implicit commit
SQL Server - yes
Sybase Adaptive Server - yes
DB2 - yes
Informix - yes
Firebird (Interbase) - yes
SQLite also appears to h...
How to explain callbacks in plain english? How are they different from calling one function from ano
How to explain callbacks in plain English? How are they different from calling one function from another function taking some context from the calling function? How can their power be explained to a novice programmer?
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Single quotes vs. double quotes in C or C++
..., that is sizeof 'a' is 4 in an architecture where ints are 32bit (and CHAR_BIT is 8), while sizeof(char) is 1 everywhere.
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Changing the maximum length of a varchar column?
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You need
ALTER TABLE YourTable ALTER COLUMN YourColumn <<new_datatype>> [NULL | NOT NULL]
But remember to specify NOT NULL explicitly if desired.
ALTER TABLE YourTable ALTER COLUMN YourColumn VARCHAR (500) NOT NULL;
If you leave it unspecified as below...
ALTER TABLE Your...
How do I append text to a file?
...ther source.
Or else entered at the keyboard, doesn't matter.
^D
Essentially, you can dump any text you want into the file. CTRL-D sends an end-of-file signal, which terminates input and returns you to the shell.
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HintPath vs ReferencePath in Visual Studio
...mit to a convention where dependency DLLs are in a "releases" svn repo and all projects point to a particular release. Since different developers have different folder structures, relative references won't work, so we came up with a scheme to use an environment variable pointing to the particular de...
Get the date (a day before current time) in Bash
... a one-liner, so cut and paste should work -- no line endings assumed. date_days_past () { days_past=${1:-0}; if ! date -v-${days_past}d +%Y%m%d 2>/dev/null; then date --date="-${days_past} day" +%Y%m%d; fi }
– Noah Spurrier
May 16 '16 at 21:29
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Scala: Abstract types vs generics
... Sommers (May 18, 2009)
Update (October2009): what follows below has actually been illustrated in this new article by Bill Venners:
Abstract Type Members versus Generic Type Parameters in Scala (see summary at the end)
(Here is the relevant extract of the first interview, May 2009, emphasis min...
How to create unit tests easily in eclipse [closed]
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Anything is standard eclipse?
– GC_
Jun 24 at 21:56
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Git diff output to file preserve coloring
...ion and open it in Notepad++ or Vim or SublimeText.
git diff > 20150203_someChanges.diff
Thanks @Monsingor
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