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Ruby: Can I write multi-line string with no concatenation?
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@Zombies: Newlines are typically allowed in SQL statements and are just treated as ordinary whitespace.
– Mark Byers
Feb 25 '10 at 22:02
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Random record in ActiveRecord
...ibute arguments will be disallowed in Rails 6.0. This method should not be called with user-provided values, such as request parameters or model attributes. Known-safe values can be passed by wrapping them in Arel.sql()."
– Trenton Tyler
Dec 26 '18 at 18:11
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A generic list of anonymous class
...{ o, o1 }.ToList();
There are lots of ways of skinning this cat, but basically they'll all use type inference somewhere - which means you've got to be calling a generic method (possibly as an extension method). Another example might be:
public static List<T> CreateList<T>(params T[] e...
How to launch Safari and open URL from iOS app
...is opened and Safari is disabled. So, even without Jailbreak, we can technically change the default web browser.
– Adrian Labbé
Sep 23 '18 at 18:21
add a comment
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How might I find the largest number contained in a JavaScript array?
...t the native implementation will be faster; in fact, the cost of the apply call can wash that out very easily.
– T.J. Crowder
Sep 4 '09 at 14:36
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Entity Framework 4 - AddObject vs Attach
... objects that do not exist in the database. The entity will get an automatically generated temporary EntityKey and its
EntityState will be set to Added. When SaveChanges is called, it will be clear to the EF that this entity needs to be inserted into the database.
ObjectContext.Attach and ObjectSe...
How do I associate a Vagrant project directory with an existing VirtualBox VM?
...llowing path:
cd .vagrant/machines/default/virtualbox
3) Create a file called id with the ID of your VM xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
4) Save the file and run vagrant up
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Difference between Key, Primary Key, Unique Key and Index in MySQL
... would use indexes to improve the speed of data retrieval. An index is typically created on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called users and you want to search for all the users which have the last name 'Smith'. Without an index, the database would have ...
Getting “Lock wait timeout exceeded; try restarting transaction” even though I'm not using a transac
...tion; autocommit does not disable transactions, it just makes them automatically commit at the end of the statement.
What is happening is, some other thread is holding a record lock on some record (you're updating every record in the table!) for too long, and your thread is being timed out.
You ca...
Use didSelectRowAtIndexPath or prepareForSegue method for UITableView?
...PathForSelectedRow() contains the correct value when prepareFroSegue... is called: tableView(_:didSelectrowAtIndexPath:) isn't called until later.
– Nicolas Miari
Jun 7 '16 at 2:21
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