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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...
What is the naming convention in Python for variable and function names?
... C# background the naming convention for variables and method names are usually either camelCase or PascalCase:
13 Answers
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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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Avoid trailing zeroes in printf()
...ing your number is in the variable num, the following function will remove all but the first N decimals, then strip off the trailing zeros (and decimal point if they were all zeros).
char str[50];
sprintf (str,"%.20g",num); // Make the number.
morphNumericString (str, 3);
: :
void morphNumericS...
Conceptually, how does replay work in a game?
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I think your initial thought was correct. To create a replay, you store all input received from the user (along with the frame number at which it was received) along with the initial seeds of any random number generators. To replay the game, you reset your PRNGs using the saved seeds and feed th...
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...
String.Replace ignoring case
I have a string called "hello world"
16 Answers
16
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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 ...