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Best practices to handle routes for STI subclasses in rails
...roller: 'person', type: 'Employee'
http://samurails.com/tutorial/single-table-inheritance-with-rails-4-part-2/
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SQL: How to get the count of each distinct value in a column?
I have a SQL table called "posts" that looks like this:
1 Answer
1
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How do I know which version of Javascript I'm using?
...ly partially, you may find 97% of ES6, 39% of ES7, kangax.github.io/compat-table/es6, and even these tables are not quite true.
– prosti
Dec 4 '16 at 21:59
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CSS fixed width in a span
... Hm, not sure. It's just a minor setback. Ended up having to use tables to get the desired effect.
– Nick Pickering
May 2 '13 at 14:10
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What is `related_name` used for in Django?
...ted name is a must in case there 2 FKs in the model that point to the same table. For example in case of Bill of material
@with_author
class BOM(models.Model):
name = models.CharField(max_length=200,null=True, blank=True)
description = models.TextField(null=True, blank=True)
tomateria...
Getting A File's Mime Type In Java
...ce this use of URL leaves a file locked, so that, for example, it is undeletable.
However, you have this:
mimeType= URLConnection.guessContentTypeFromName(file.getName());
and also the following, which has the advantage of going beyond mere use of file extension, and takes a peek at content
In...
Setting custom UITableViewCells height
I am using a custom UITableViewCell which has some labels, buttons and image views to be displayed. There is one label in the cell whose text is a NSString object and the length of string could be variable. Due to this, I cannot set a constant height to the cell in the UITableView 's heightForCe...
Call a stored procedure with parameter in c#
...eries in a variety of fashions.
A stored procedure is a pre-compiled executable object that contains one or more SQL statements. In many cases stored procedures accept input parameters and return multiple values . Parameter values can be supplied if a stored procedure is written to accept them. A s...
PostgreSQL ERROR: canceling statement due to conflict with recovery
... will be canceled more often.
You can work around this by starting a repeatable read transaction on primary which does a dummy query and then sits idle while a real query is run on secondary. Its presence will prevent vacuuming of old row versions on primary.
More on this subject and other workaro...
What is the benefit of zerofill in MySQL?
....
Here is some example SQL that demonstrates the use of ZEROFILL:
CREATE TABLE yourtable (x INT(8) ZEROFILL NOT NULL, y INT(8) NOT NULL);
INSERT INTO yourtable (x,y) VALUES
(1, 1),
(12, 12),
(123, 123),
(123456789, 123456789);
SELECT x, y FROM yourtable;
Result:
x y
00000001 ...