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Rails migration for has_and_belongs_to_many join table
How do I do a script/generate migration to create a join table for a has_and_belongs_to_many relationship?
6 Answers
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Create unique constraint with null columns
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Create two partial indexes:
CREATE UNIQUE INDEX favo_3col_uni_idx ON favorites (user_id, menu_id, recipe_id)
WHERE menu_id IS NOT NULL;
CREATE UNIQUE INDEX favo_2col_uni_idx ON favorites (user_id, recipe_id)
WHERE menu_id IS NULL;
This way,...
how to add records to has_many :through association in rails
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I think you can simply do this:
@cust = Customer.new(params[:customer])
@cust.houses << House.find(params[:house_id])
Or when creating a new house for a customer:
@cust = Customer.new(params[:customer])
@cust.houses...
Add new item count to icon on button - Android
...have functional app but wonder how to even approach this? Particulary, I'm interested in how to show Number of "New" items under tabs. What I KNOW how to do - is create new icons with red dots and just display them when new stuff available.
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YouTube API to fetch all videos on a channel
We need a video list by channel name of YouTube (using the API).
14 Answers
14
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Start an Activity with a parameter
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Put an int which is your id into the new Intent.
Intent intent = new Intent(FirstActivity.this, SecondActivity.class);
Bundle b = new Bundle();
b.putInt("key", 1); //Your id
intent.putExtras(b); //Put your id to your next Intent
st...
dynamically add and remove view to viewpager
(I figured out a solution - please see my post in the Answer section below.)
8 Answers
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Django database query: How to get object by id?
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If you want to get an object, using get() is more straightforward:
obj = Class.objects.get(pk=this_object_id)
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How to implement a unique index on two columns in rails
I have a table and I'm trying to add a unique index on two columns. Those columns are also indexed. So my question is if I just can remove the indexes who were just for one column or if I have to use all three indexes:
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mysql :: insert into table, data from another table?
I was wondering if there is a way to do this purely in sql:
5 Answers
5
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