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How to check if a table exists in a given schema
... (like OIDs) gets lost in translation from the system catalogs - which actually carry all information.
System catalogs
Your question was:
How to check whether a table exists?
SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHE...
Ruby on Rails - Import Data from a CSV file
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The smarter_csv gem was specifically created for this use-case: to read data from CSV file and quickly create database entries.
require 'smarter_csv'
options = {}
SmarterCSV.process('input_file.csv', options) do |chunk|
chunk.each do |data_hash|
...
How to restore to a different database in sql server?
...mpCopy with the contents of your.bak.
Example (restores a backup of a db called 'creditline' to 'MyTempCopy';
RESTORE FILELISTONLY FROM DISK='e:\mssql\backup\creditline.bak'
>LogicalName
>--------------
>CreditLine
>CreditLine_log
RESTORE DATABASE MyTempCopy FROM DISK='e:\mssql\backu...
IOException: read failed, socket might closed - Bluetooth on Android 4.3
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I have finally found a workaround. The magic is hidden under the hood of the BluetoothDevice class (see https://github.com/android/platform_frameworks_base/blob/android-4.3_r2/core/java/android/bluetooth/BluetoothDevice.java#L1037).
N...
Open a new tab in gnome-terminal using command line [closed]
...ferent commands in different tabs. No matter where I add the commands they all get executed in the first tab. Can you include a solution for this?
– Calin
May 3 '11 at 21:25
10
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ASP.NET MVC 3: Override “name” attribute with TextBoxFor
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Rob, actually there is a much simpler way. Instead of name, use Name:
@Html.TextBoxFor(x => x.Data, new { Name = Model.Key + "_Data", id = Model.Key + "_Data" })
...
How do I remove documents using Node.js Mongoose?
...you don't feel like iterating, try FBFriendModel.find({ id:333 }).remove( callback ); or FBFriendModel.find({ id:333 }).remove().exec();
mongoose.model.find returns a Query, which has a remove function.
Update for Mongoose v5.5.3 - remove() is now deprecated. Use deleteOne(), deleteMany() or findO...
Calculate the median of a billion numbers
...bably too late if this had been an interview, but never mind:
Machine 1 shall be called the "control machine", and for the sake of argument either it starts with all the data, and sends it in equal parcels to the other 99 machines, or else the data starts evenly distributed between the machines, an...
How to slice an array in Bash
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There is also a convenient shortcut to get all elements of the array starting with specified index. For example "${A[@]:1}" would be the "tail" of the array, that is the array without its first element.
version=4.7.1
A=( ${version//\./ } )
echo "${A[@]}" # 4 7 1
B...
Given a view, how do I get its viewController?
...nd
This macro avoids category pollution:
#define UIViewParentController(__view) ({ \
UIResponder *__responder = __view; \
while ([__responder isKindOfClass:[UIView class]]) \
__responder = [__responder nextResponder]; \
(UIViewController *)__responder; \
})
...