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MySQL: What's the difference between float and double?
...| double | decimal |
+-------------------+------------+-----+
|2.5999999046325684 | 2.6 | 2.60000 |
1.3 float MULTIPLIED by 1.3 of different types:
| float | double | decimal |
+--------------------+--------------------+--------------+
| 1.6899998760223411 | 1.690...
Concatenate two string literals
...itial element.
So, when you try to do "Hello" + ",world", what you're really trying to do is add two const char*s together, which isn't possible (what would it mean to add two pointers together?) and if it was it wouldn't do what you wanted it to do.
Note that you can concatenate string liter...
Sql query to insert datetime in SQL Server
... I used the SQL query below to test the format, and it does indeed work in all SQL languages in sys.syslanguages:
declare @sql nvarchar(4000)
declare @LangID smallint
declare @Alias sysname
declare @MaxLangID smallint
select @MaxLangID = max(langid) from sys.syslanguages
set @LangID = 0
while @...
How do I get the full path to a Perl script that is executing?
...me of the script during execution. I discovered that depending on how you call the script $0 varies and sometimes contains the fullpath+filename and sometimes just filename . Because the working directory can vary as well I can't think of a way to reliably get the fullpath+filename of the scr...
Symfony 2: How do I check if a user is not logged in inside a template?
...any user is logged in.
{% if app.user %}
# user is logged in (any and all users, regardless of ROLE_*)
{% elseif not app.user %}
# user is not logged in (note the `not` in the `elseif` statement)
{% endif %}
Checking authentication status
You can use the is_granted() method to check fo...
How do I “source” something in my .vimrc file?
...
Sourcing a file is 'executing' it. Essentially, each line of the file is considered a command. Sourcing it is the same as typing each command in order. You source with the command :source (usually shortened to :so).
So if you source myStuff.vim
:so myStuff.vim
an...
Convert PDF to clean SVG? [closed]
...t they often lose the font data, but don't seem to approximate a good, installed font. How does PDF display it if SVG can't?
– DanRedux
Apr 23 '12 at 21:30
...
What is a .snk for?
What is a .snk file for? I know it stands for Strongly Named Key , but all explanations of what it is and how it works goes over my head.
...
Extracting hours from a DateTime (SQL Server 2005)
...e #6 here blogs.sqlsentry.com/aaronbertrand/… and sqlblog.com/blogs/aaron_bertrand/archive/2011/09/20/…
– Aaron Bertrand
Oct 6 '14 at 19:44
4
...
How to make rounded percentages add up to 100%
...55310199789695, 8.780231335436383, 8.04416403785489, 0]. The last one logically returns -1. I thought of the following solution really quickly but there's probably something better: jsfiddle.net/0o75bw43/1
– Cruclax
Aug 5 '16 at 16:39
...