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Why are dashes preferred for CSS selectors / HTML attributes?
...ops.
Also, using hyphens allows you to take advantage of the |= attribute selector, which selects any element containing the text, optionally followed by a dash:
span[class|="em"] { font-style: italic; }
This would make the following HTML elements have italic font-style:
<span class="em">...
How to create a database from shell command?
... I get this error ERROR 1046 (3D000) at line 27: No database selected when I run echo "create database databasename" | mysql -u -u username -p command
– keerthi
Mar 15 '13 at 5:16
...
Difference between partition key, composite key and clustering key in Cassandra?
...KEY:
insert into stackoverflow_simple (key, data) VALUES ('han', 'solo');
select * from stackoverflow_simple where key='han';
table content
key | data
----+------
han | solo
COMPOSITE/COMPOUND KEY can retrieve "wide rows" (i.e. you can query by just the partition key, even if you have clusteri...
Maximum number of records in a MySQL database table
...g with multiple billions of entries? (which would probably just make your select statements melt down long before then)
– Kzqai
Apr 26 '10 at 19:35
2
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Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
Removing all empty elements from a hash / YAML?
...mplementation is not recursive. As a curiosity, they implemented it using #select instead of #delete_if for performance reasons. See here for the benchmark.
In case you want to backport it to your Rails 3 app:
# config/initializers/rails4_backports.rb
class Hash
# as implemented in Rails 4
# ...
Reference - What does this error mean in PHP?
...
mysql_fetch_array() expects parameter 1 to be resource, boolean given in select
All "mysql_fetch_array() expects parameter 1 to be resource, boolean given" Questions on Stackoverflow
Related Errors:
Warning: [function] expects parameter 1 to be resource, boolean given
Other mysql* functions ...
unresolved reference to object [INFORMATION_SCHEMA].[TABLES]
...database reference to master:
Under the project, right-click References.
Select Add database reference....
Select System database.
Ensure master is selected.
Press OK.
Note that it might take a while for VS to update.
sh...
How to change Android version and code version number?
...Ctrl+Alt+Shift+S in android studio or go to File > Project Structure...
Select app on left side and select falvors tab on right side on default config change version code , name and etc...
share
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How to delete a file from SD card?
...
File file = new File(selectedFilePath);
boolean deleted = file.delete();
where selectedFilePath is the path of the file you want to delete - for example:
/sdcard/YourCustomDirectory/ExampleFile.mp3
...