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Why does NULL = NULL evaluate to false in SQL server
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I disagree that null signifies "unknown". What it actually means is "no data". That might be used to represent the case where information is not known, but it is actually more likely to be used to indicate that something doesn't exist. To continue your example: What is Frank's m...
How to modify a text file?
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This is an operating system thing, not a Python thing. It is the same in all languages.
What I usually do is read from the file, make the modifications and write it out to a new file called myfile.txt.tmp or something like that. This is better than reading the whole file into memory because the f...
How to change a nullable column to not nullable in a Rails migration?
...s:
# Make sure no null value exist
MyModel.where(date_column: nil).update_all(date_column: Time.now)
# Change the column to not allow null
change_column :my_models, :date_column, :datetime, null: false
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How to grep Git commit diffs or contents for a certain word?
In a Git code repository I want to list all commits that contain a certain word. I tried this
8 Answers
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What's wrong with Java Date & Time API? [closed]
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answered Dec 28 '09 at 13:32
waxwingwaxwing
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jQuery: Get height of hidden element in jQuery
...ke a charm!
– Jayen
Jun 4 '14 at 10:32
Now I understand why it's height not shown with display:none elements. Thanks a...
How to split text without spaces into list of words?
...el the distribution of the output. A good first approximation is to assume all words are independently distributed. Then you only need to know the relative frequency of all words. It is reasonable to assume that they follow Zipf's law, that is the word with rank n in the list of words has probabilit...
FIND_IN_SET() vs IN()
...FROM orders
CROSS JOIN
(
SELECT 1 AS pos
UNION ALL
SELECT 2 AS pos
UNION ALL
SELECT 3 AS pos
UNION ALL
SELECT 4 AS pos
UNION ALL
SELECT 5 AS pos
) q
JOIN company
ON companyID = CAST(NULLIF(SUBSTRI...
Set Locale programmatically
...ocale to the front of the list set.add(locale); LocaleList all = LocaleList.getDefault(); for (int i = 0; i < all.size(); i++) { // append other locales supported by the user set.add(all.get(i)); } Locale[] locales = set.toArray(new ...
String.Replace ignoring case
I have a string called "hello world"
16 Answers
16
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