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Where does PostgreSQL store the database?
...e tablespaces, which might not be in that data directory, use this query.
SELECT * FROM pg_tablespace;
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Getting the encoding of a Postgres database
...
A programmatic solution:
SELECT pg_encoding_to_char(encoding) FROM pg_database WHERE datname = 'yourdb';
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How to recognize USB devices in Virtualbox running on a Linux host? [closed]
...y success. It seems they are not detected by Virtualbox itself, since if I select the guest from the Virtualbox home (I'm using a Windows XP 3 guest), choose Settings -> USB -> Add filter from device, no devices is listed, even if an USB pen is attached and recognized by my Lubuntu 13.10. If i run t...
Login failed for user 'DOMAIN\MACHINENAME$'
...curity >> Logins and right click on NT AUTHORITY\NETWORK SERVICE and select Properties
In newly opened screen of Login Properties, go to the “User Mapping” tab. Then, on the “User Mapping” tab, select the desired database – especially the database for which this error message is dis...
How can I deploy an iPhone application from Xcode to a real iPhone device?
...w the use of this certificate:
Launch Keychain Access.app. With no items selected, from the Keychain menu select Certificate Assistant, then Create a Certificate.
Name: iPhone Developer
Certificate Type: Code Signing
Let me override defaults: Yes
Click Continue
Validity: 3650 days
Click Cont...
postgresql COUNT(DISTINCT …) very slow
...
You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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C#/Linq: Apply a mapping function to each element in an IEnumerable?
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You can just use the Select() extension method:
IEnumerable<int> integers = new List<int>() { 1, 2, 3, 4, 5 };
IEnumerable<string> strings = integers.Select(i => i.ToString());
Or in LINQ syntax:
IEnumerable<int> in...
Compare dates in MySQL
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You can try below query,
select * from players
where
us_reg_date between '2000-07-05'
and
DATE_ADD('2011-11-10',INTERVAL 1 DAY)
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How to change folder with git bash?
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Go to the directory manually and do right click → Select 'Git bash' option.
Git bash terminal automatically opens with the intended directory. For example, go to your project folder. While in the folder, right click and select the option and 'Git bash'. It will open automat...
Eclipse: enable assertions
...to Preferences.
Choose Java, and then Installed JREs from the left panel.
Select your JRE, and then click the Edit... button in the right panel.
In the Default VM arguments field, add -ea.
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