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How to declare a variable in MySQL?
... refer to a variable that has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BET...
Rails create or update magic?
...
Rails 6
Rails 6 added an upsert and upsert_all methods that deliver this functionality.
Model.upsert(column_name: value)
[upsert] It does not instantiate any models nor does it trigger Active Record callbacks or validations.
Rails 5, 4, and 3
Not ...
How can I split a JavaScript string by white space or comma?
...'s both more strict than what I suggest (only one comma allowed, in front) and more loose (split on all whitespace) than what the OP asked for. IMHO it would be simply worse -- consider the input spaces , before commas.
– Jon
Apr 27 '12 at 7:52
...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...o do an upsert, which is what MySQL calls INSERT ... ON DUPLICATE UPDATE and the standard supports as part of the MERGE operation.
...
How to change the value of ${user} variable used in Eclipse templates
...our best bet is to redefine the java user.name variable either at your command line, or using the eclipse.ini file in your eclipse install root directory.
This seems to work fine for me:
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256M
-vmargs
-Dosgi.requiredJavaVersion=1.5
-Duser.name...
OR is not supported with CASE Statement in SQL Server
...
For the second case, why does only 'IN' work and not '='?
– Han
Jun 13 '16 at 14:53
26
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Hidden features of Perl?
...ation when looping through the records (usually lines) returned by a file handle, without using a flag variable:
while(<$fh>)
{
next if 1..1; # skip first record
...
}
Run perldoc perlop and search for "flip-flop" for more information and examples.
...
What is SOA “in plain english”? [closed]
...sh what is SOA all about ? I hear SOA here, SOA there but I cannot understand exacly what it is and what is used for. Was it some simple concept and later evolved into something huge or what?
...
Gulps gulp.watch not triggered for new or deleted files?
...w. It did not when the question was asked.
The rest of my answer still stands: gulp-watch is usually a better solution because it lets you perform specific actions only on the files that have been modified, while gulp.watch only lets you run complete tasks. For a project of a reasonable size, thi...
NoSQL (MongoDB) vs Lucene (or Solr) as your database
... similarity with how to treat items as "Documents", just like Lucene does (and users of Solr).
10 Answers
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