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Delete multiple objects in django
I need to select several objects to be deleted from my database in django using a webpage. There is no category to select from so I can't delete from all of them like that. Do I have to implement my own delete form and process it in django or does django have a way to already do this? As its impleme...
Copy a table from one database to another in Postgres
... follow these steps:
In pgAdmin, right click the table you want to move, select "Backup"
Pick the directory for the output file and set Format to "plain"
Click the "Dump Options #1" tab, check "Only data" or "only Schema" (depending on what you are doing)
Under the Queries section, click "Use Colu...
MySQL Select Query - Get only first 10 characters of a value
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Using the below line
SELECT LEFT(subject , 10) FROM tbl
MySQL Doc.
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Spring Boot JPA - configuring auto reconnect
...1.3
spring.datasource.testOnBorrow=true
spring.datasource.validationQuery=SELECT 1
As djxak noted in the comment, 1.4+ defines specific namespaces for the four connections pools Spring Boot supports: tomcat, hikari, dbcp, dbcp2 (dbcp is deprecated as of 1.5). You need to check which connection po...
Correct way to quit a Qt program?
...ose your application from main() you can use this code
int main(int argc, char *argv[]){
QApplication app(argc, argv);
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if(!QSslSocket::supportsSsl()) return app.exit(0);
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return app.exec();
}
The program will terminated if OpenSSL is not installed
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how to set radio option checked onload with jQuery
...rop. Also there's no need for the extra filter, you can just combine the 2 selectors e.g. $("input[name=gender][value=Male]").prop("checked", true);
– jackocnr
Apr 2 '14 at 21:56
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Database, Table and Column Naming Conventions? [closed]
...lar "entity names" in queries, that's what I would use table aliases for:
SELECT person.Name
FROM People person
A bit like LINQ's "from person in people select person.Name".
As for 2, 3 and 4, I agree with @Lars.
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MySQL IF NOT NULL, then display 1, else display 0
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SELECT c.name, IF(a.addressid IS NULL,0,1) AS addressexists
FROM customers c
LEFT JOIN addresses a ON c.customerid = a.customerid
WHERE customerid = 123
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How to write a large buffer into a binary file in C++, fast?
...stream("file.binary", std::ios::out | std::ios::binary);
myfile.write((char*)&data[0], bytes);
myfile.close();
auto endTime = std::chrono::high_resolution_clock::now();
return std::chrono::duration_cast<std::chrono::milliseconds>(endTime - startTime).count();
}
long long ...
Write string to output stream
...de it. You can do that manually (as you suggest) using the String.getBytes(Charset) method, but you should avoid the String.getBytes() method, because that uses the default encoding of the JVM, which can't be reliably predicted in a portable way.
The usual way to write character data to a stream, t...