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MySQL load NULL values from CSV data
...one, two, three, @vfour, five)
SET four = NULLIF(@vfour,'')
;
If they're all possibly empty, then you'd read them all into variables and have multiple SET statements, like this:
LOAD DATA INFILE '/tmp/testdata.txt'
INTO TABLE moo
FIELDS TERMINATED BY ","
LINES TERMINATED BY "\n"
(@vone, @vtwo, @v...
Delegates: Predicate vs. Action vs. Func
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Predicate: essentially Func<T, bool>; asks the question "does the specified argument satisfy the condition represented by the delegate?" Used in things like List.FindAll.
Action: Perform an action given the arguments. Very general purpos...
Organizing a multiple-file Go project [closed]
...eath src, you can simply place your project mypack, and underneath that is all of your .go files including the mypack_test.go
go build will then build into the root level pkg and bin.
So your GOPATH might look like this:
~/projects/
bin/
pkg/
src/
mypack/
foo.go
...
Algorithm for classifying words for hangman difficulty levels as “Easy”,“Medium”, or “Hard”
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1. Introduction
Here's a way to approach this problem systematically: if you have an algorithm that plays hangman well, then you can take the difficulty of each word to be the number of wrong guesses that your program would take if guessing that word.
2. Aside on hangman strategy
There'...
if/else in a list comprehension
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You can totally do that. It's just an ordering issue:
[unicode(x.strip()) if x is not None else '' for x in row]
In general,
[f(x) if condition else g(x) for x in sequence]
And, for list comprehensions with if conditions only,
[f...
How to get ERD diagram for an existing database?
...that.
Description:
The references graph is a great feature as it automatically renders all primary/foreign key mappings (also called referential integrity constraints) in a graph style. The table nodes and relations are layed out automatically, with a number of layout modes available. The resulting...
How to adjust layout when soft keyboard appears
... android:textAppearance="?android:attr/textAppearanceSmall" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true...
How can I have ruby logger log output to stdout as well as file?
...g.log", "a")
Logger.new MultiIO.new(STDOUT, log_file)
Every time Logger calls puts on your MultiIO object, it will write to both STDOUT and your log file.
Edit: I went ahead and figured out the rest of the interface. A log device must respond to write and close (not puts). As long as MultiIO re...
How to alter a column and change the default value?
...t use this if you need to change only the DEFAULT value. This will process all the rows of the table for nothing (very long on huge tables). Use instead ALTER TABLE <table_name> ALTER COLUMN <column_name> SET DEFAULT <value> which is instant.
– dolmen
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Google Chromecast sender error if Chromecast extension is not installed or using incognito
...hromecast sender in Chrome Incognito or if Chromecast extension is not installed:
5 Answers
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