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MySQL: What's the difference between float and double?
...INSERT INTO `test` values (1.2,1.2,1.2,1.2);
The table showing like this:
SELECT * FROM `test`;
+------+------+------+------+
| fla | flb | dba | dbb |
+------+------+------+------+
| 1.2 | 1.2 | 1.20 | 1.20 |
+------+------+------+------+
See the difference?
We try to next example:
SELECT ...
How do you list all triggers in a MySQL database?
...w triggers;
or you can access the INFORMATION_SCHEMA table directly by:
select trigger_schema, trigger_name, action_statement
from information_schema.triggers
You can do this from version 5.0.10 onwards.
More information about the TRIGGERS table is here.
...
Using semicolon (;) vs plus (+) with exec in find
...+
This variant of the -exec option runs the specified command on
the selected files, but the command line is built by appending
each selected file name at the end; the total number of
invocations of the command will be much less than the number of
matched files. The command line is built...
Remove duplicated rows using dplyr
...ce(from = 1, to = 1)
Or maybe a variation of unique() that would let you select which
variables to use:
df %>% unique(x, y)
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Best way to get InnerXml of an XElement?
...ToString();
String.Join on array:
return String.Join("", parent.Nodes().Select(x => x.ToString()).ToArray());
String.Concat on array:
return String.Concat(parent.Nodes().Select(x => x.ToString()).ToArray());
I haven't shown the "Plain old System.Xml" algorithm here as it's just calling...
Is it possible to group projects in Eclipse?
...You define a working set and then add some projects to it. Later you could select a working set and only the projects you selected earlier are shown in project explorer.
Simpl grouping to reduce clutter.
http://help.eclipse.org/galileo/index.jsp?topic=/org.eclipse.platform.doc.user/concepts/cworkse...
“inconsistent use of tabs and spaces in indentation”
...
With the IDLE editor you can use this:
Menu Edit → Select All
Menu Format → Untabify Region
Assuming your editor has replaced 8 spaces with a tab, enter 8 into the input box.
Hit select, and it fixes the entire document.
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What's an easy way to read random line from a file in Unix command line?
...he whole file needs to get shuffled by sort before piping it to head. shuf selects random lines from the file, instead and is much faster for me.
– Bengt
Nov 25 '12 at 17:33
1
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Multiline strings in VB.NET
...
I used this variant:
Dim query As String = <![CDATA[
SELECT
a.QuestionID
FROM
CR_Answers a
INNER JOIN
CR_Class c ON c.ClassID = a.ClassID
INNER JOIN
CR_Questions q ON q.QuestionID = a.QuestionID
...
Position a CSS background image x pixels from the right?
...
This should be the selected as the "Correct answer". According to MDN it's supported in IE9+ and all other browsers, which is great! developer.mozilla.org/en-US/docs/Web/CSS/…
– fregante
Sep 27 '13 at 0:...