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MySQL: selecting rows where a column is null
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NULL = NULL is not really FALSE - it's NULL again. But it's not TRUE either, so IF(NULL = NULL) won't execute.
– Konerak
Jan 12 '11 at 19:50
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MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update
as the title says, I want to perform a find (one) for a document, by _id, and if doesn't exist, have it created, then whether it was found or was created, have it returned in the callback.
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How to loop through a plain JavaScript object with the objects as members?
How can I loop through all members in a JavaScript object including values that are objects.
24 Answers
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How to parse JSON in Scala using standard Scala classes?
... {
"languages": [{
"name": "English",
"is_active": true,
"completeness": 2.5
}, {
"name": "Latin",
"is_active": false,
"completeness": 0.9
}]
}
""".stripMargin
val result = for {
Some(M(m...
Java equivalent to #region in C#
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Actually this can be achieved. If you scroll down on this post "Yaqub Ahmad" explains how to get this functionality. Also here is a link (kosiara87.blogspot.com/2011/12/…) that shows you how to add it to your existing eclipse e...
Filter rows which contain a certain string
...n easily extend to more than one column.
Below also a solution with filter_all in order to find the string in any column,
using diamonds as example, looking for the string "V"
library(tidyverse)
String in only one column
# for only one column... extendable to more than one creating a column list in...
Why would finding a type's initializer throw a NullReferenceException?
....cs:
(196c.1874): Access violation - code c0000005 (first chance)
mscorlib_ni!System.RuntimeType.GetConstructorImpl(System.Reflection.BindingFlags, System.Reflection.Binder, System.Reflection.CallingConventions, System.Type[], System.Reflection.ParameterModifier[])+0xa3:
000007fe`e5735403 488b4608 ...
How to elegantly deal with timezones
...t is that inside the DB, date/times are stored in UTC. When on the server, all date/times should be dealt with in UTC. However, I see three problems that I'm trying to overcome:
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Convert unix time to readable date in pandas dataframe
...12.15
3 1349979305 12.19
4 1350065705 12.15
In [25]: df['date'] = pd.to_datetime(df['date'],unit='s')
In [26]: df.head()
Out[26]:
date price
0 2012-10-08 18:15:05 12.08
1 2012-10-09 18:15:05 12.35
2 2012-10-10 18:15:05 12.15
3 2012-10-11 18:15:05 12.19
4 2012-10-12 18:15:...
How to programmatically determine the current checked out Git branch [duplicate]
...ions/git-completion.bash does that for bash prompt in __git_ps1. Removing all extras like selecting how to describe detached HEAD situation, i.e. when we are on unnamed branch, it is:
branch_name="$(git symbolic-ref HEAD 2>/dev/null)" ||
branch_name="(unnamed branch)" # detached HEAD
branc...