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Recommended way to embed PDF in HTML?
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if you want to get sure it will be shown instead of auto download the pdf (as it happend to me) add type='application/pdf' to the embed tag
– Hassek
Sep 4 '12 at 15:44
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How to drop SQL default constraint without knowing its name?
In Microsoft SQL Server, I know the query to check if a default constraint exists for a column and drop a default constraint is:
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How do I make a column unique and index it in a Ruby on Rails migration?
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add_index :table_name, [:column_name_a, :column_name_b], unique: true
If you get "index name... is too long", you can add name: "whatever" to the add_index method to make the name shorter.
For fine-grained control, there's a "execute" method that executes straight SQL.
That's it!
If you are...
How do I fix certificate errors when running wget on an HTTPS URL in Cygwin?
... solution after all.
First, you need to install the cygwin package ca-certificates via Cygwin's setup.exe to get the certificates.
Do NOT use curl or similar hacks to download certificates (as a neighboring answer advices) because that's fundamentally insecure and may compromise the system.
Seco...
Why do you need to create a cursor when querying a sqlite database?
...be used to fetch data from the DBMS into an
application but also to identify a row in a table to be updated or
deleted. The SQL:2003 standard defines positioned update and
positioned delete SQL statements for that purpose. Such statements do
not use a regular WHERE clause with predicates. In...
Merge two (or more) lists into one, in C# .NET
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Assuming you want a list containing all of the products for the specified category-Ids, you can treat your query as a projection followed by a flattening operation. There's a LINQ operator that does that: SelectMany.
// implicitly List<Product>
var products = new[] { CategoryId1, Categ...
How do you underline a text in Android XML?
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If you are using a string resource xml file (supports HTML tags), it can be done using<b> </b>, <i> </i> and <u> </u>.
<resources>
<string name="your_string_here">
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Efficiency of purely functional programming
...system.
There are a few caveats to be made about this paper. The most significant is that it does not address lazy functional languages, such as Haskell. Bird, Jones and De Moor [1997] demonstrate that the problem constructed by Pippenger can be solved in a lazy functional language in O(n) time, bu...
How to extract URL parameters from a URL with Ruby or Rails?
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Good find. If you have simple params (non-nested) and are performance sensitive, Rack::Utils.parse_query might be of interest. The code is worth reading: github.com/rack/rack/blob/master/lib/rack/utils.rb
– Levi
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Rails has_and_belongs_to_many migration
...rom the docs:
There is also a generator which will produce join tables if JoinTable
is part of the name:
Your migration file (note the :id => false; it's what prevents the creation of a primary key):
Rails 3
class CreateRestaurantsUsers < ActiveRecord::Migration
def self.up
c...