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PG undefinedtable error relation users does not exist
...migrations. It will only use the
contents of the current schema.rb file. If a migration can't be rolled back,
rake db:reset may not help you. To find out more about dumping the schema see
Schema Dumping and You section. Rails Docs
If the trick doesn't help, drop the database, then re-create ...
What is a database transaction?
... than possible) explanation of a transaction as applied to computing (even if copied from Wikipedia)?
11 Answers
...
Variable name as a string in Javascript
...usfx you can swap out const for let or var and it works just the same. But if you're using a transpiler for the object destructuring in the first place, it probably supports const already.
– SethWhite
Dec 12 '17 at 15:19
...
Catch checked change event of a checkbox
...ype="checkbox" id="something" />
$("#something").click( function(){
if( $(this).is(':checked') ) alert("checked");
});
Edit: Doing this will not catch when the checkbox changes for other reasons than a click, like using the keyboard. To avoid this problem, listen to changeinstead of click.
...
What is the point of “final class” in Java?
...of all, I recommend this article: Java: When to create a final class
If they do, when do they use it so I can understand it better and know when to use it.
A final class is simply a class that can't be extended.
(It does not mean that all references to objects of the class would act as if t...
How do I execute a stored procedure once for each row returned by query?
...ter than manual while-loops; more details in this SO question
ADDENDUM 2: if you will be processing more than just a few records, pull them into a temp table first and run the cursor over the temp table; this will prevent SQL from escalating into table-locks and speed up operation
ADDENDUM 3: and ...
Install a Windows service using a Windows command prompt?
...
If it is the x64 compiled service, use "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\installutil.exe".
– nme
Feb 23 '16 at 10:10
...
How to reset AUTO_INCREMENT in MySQL?
...value less than or equal
to any that have already been used. For MyISAM, if the value is less
than or equal to the maximum value currently in the AUTO_INCREMENT
column, the value is reset to the current maximum plus one. For
InnoDB, if the value is less than the current maximum value in the
...
What is the purpose of AsQueryable()?
...ns that can apply to either in-memory sequences or external data sources. If you write your help methods to use IQueryable entirely you can just use AsQueryable on all enumerables to use them. This allows you to avoid writing two separate versions of very generalized helper methods.
It allows you ...
How to put a new line into a wpf TextBlock control?
... a new line in the data:
<data>Foo bar baz
baz bar</data>
If that does not work you might need to parse the string manually.
If you need direct XAML that's easy by the way:
<TextBlock>
Lorem <LineBreak/>
Ipsum
</TextBlock>
...