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Should arrays be used in C++?
Since std::list and std::vector exist, is there a reason to use traditional C arrays in C++, or should they be avoided, just like malloc ?
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How to check if field is null or empty in MySQL?
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end as field1
from tablename
If you only want to check for null and not for empty strings then you can also use ifnull() or coalesce(field1, 'empty'). But that is not suitable for empty strings.
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Entity Framework. Delete all rows in table
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For those that are googling this and ended up here like me, this is how you currently do it in EF5 and EF6:
context.Database.ExecuteSqlCommand("TRUNCATE TABLE [TableName]");
Assuming context is a System.Data.Entity.DbContext
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Best way to convert text files between character sets?
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Stand-alone utility approach
iconv -f ISO-8859-1 -t UTF-8 in.txt > out.txt
-f ENCODING the encoding of the input
-t ENCODING the encoding of the output
You don't have to specify either of these arguments. They will de...
How do you test running time of VBA code?
... class, call it CTimer say, then you can make an instance somewhere global and just call .StartCounter and .TimeElapsed
Option Explicit
Private Type LARGE_INTEGER
lowpart As Long
highpart As Long
End Type
Private Declare Function QueryPerformanceCounter Lib "kernel32" (lpPerformanceCount ...
Spring @Transaction method call by the method within the same class, does not work?
...ring Transaction. Something that I found really odd, probably I did understand this properly.
8 Answers
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Regex doesn't work in String.matches()
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Welcome to Java's misnamed .matches() method... It tries and matches ALL the input. Unfortunately, other languages have followed suit :(
If you want to see if the regex matches an input text, use a Pattern, a Matcher and the .find() method of the matcher:
Pattern p = Pattern.comp...
Apache Spark: map vs mapPartitions?
What's the difference between an RDD's map and mapPartitions method? And does flatMap behave like map or like mapPartitions ? Thanks.
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How does SIGINT relate to the other termination signals such as SIGTERM, SIGQUIT and SIGKILL?
...tion signals usually have the following order (according to many MAN pages and the POSIX Spec):
6 Answers
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Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
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So I guess it is safer to define a variable with the result of that command as your empty sha1 tree (instead of relying of a "well known value").
Note: Git 2.25.1 (Feb. 2020) proposes in commit 9c8a294:
empty_tree=$(git mktree </dev/null)
# Windows:
git mktree <NUL
And adds:
As a hi...