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What is an index in SQL?
...refman/5.0/en/mysql-indexes.html
An index can be used to efficiently find all rows matching some column in your query and then walk through only that subset of the table to find exact matches. If you don't have indexes on any column in the WHERE clause, the SQL server has to walk through the whole ...
How to delete all files and folders in a directory?
Using C#, how can I delete all files and folders from a directory, but still keep the root directory?
29 Answers
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Loop through all the files with a specific extension
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It will if it actually matches any files. You need to use shopt -s nullglob so that a non-matching pattern expands to the empty sequence rather than be treated literally.
– chepner
Aug 1 '15 at 23:08
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How to change language of app when user selects language?
...ange in language. The locale you applied will not be changed until you manually change it again.
public void setLocale(String lang) {
Locale myLocale = new Locale(lang);
Resources res = getResources();
DisplayMetrics dm = res.getDisplayMetrics();
Configuration conf = res.getConf...
How does Java Garbage Collection work with Circular References?
... method that prints out a unique id for the object. You'll be able to see all the objects that reference each other get collected.
– Bill the Lizard
Dec 15 '09 at 20:45
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Postgres and Indexes on Foreign Keys and Primary Keys
Does Postgres automatically put indexes on Foreign Keys and Primary Keys? How can I tell? Is there a command that will return all indexes on a table?
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HTML encoding issues - “” character showing up instead of “ ”
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Found another source This works in all browsers
– Richard Ayotte
Feb 19 '12 at 12:57
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Search text in fields in every table of a MySQL database
I want to search in all fields from all tables of a MySQL database a given string, possibly using syntax as:
24 Answers
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Print only?
How do I print the indicated div (without manually disabling all other content on the page)?
30 Answers
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Why always ./configure; make; make install; as 3 separate steps?
...guration. Also ./configure checks for missing libraries that should be installed. Anything wrong here causes not to build your application. That's why distros have packages that are installed on different places, because every distro thinks it's better to install certain libraries and files to certa...