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How to COUNT rows within EntityFramework without loading contents?
...y syntax:
var count = (from o in context.MyContainer
where o.ID == '1'
from t in o.MyTable
select t).Count();
Method syntax:
var count = context.MyContainer
.Where(o => o.ID == '1')
.SelectMany(o => o.MyTable)
.Coun...
scopes with lambda and arguments in Rails 4 style?
...
I think it should be:
scope :find_lazy, -> (id) { where(id: id) }
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How to delete from multiple tables in MySQL?
...ement.
DELETE p, pa
FROM pets p
JOIN pets_activities pa ON pa.id = p.pet_id
WHERE p.order > :order
AND p.pet_id = :pet_id
Alternatively you can use...
DELETE pa
FROM pets_activities pa
JOIN pets p ON pa.id = p.pet_id
WHERE p.order > :order
AND p.pet_...
How to get CSS to select ID that begins with a string (not in Javascript)?
...
[id^=product]
^= indicates "starts with". Conversely, $= indicates "ends with".
The symbols are actually borrowed from Regex syntax, where ^ and $ mean "start of string" and "end of string" respectively.
See the specs for ...
SQL Server insert if not exists best practice
...k or so? (remember this only takes a few seconds)
– Didier Levy
Mar 14 '11 at 12:35
3
@Didier Lev...
Include intermediary (through model) in responses in Django Rest Framework
...
class MembershipSerializer(serializers.HyperlinkedModelSerializer):
id = serializers.Field(source='group.id')
name = serializers.Field(source='group.name')
class Meta:
model = Membership
fields = ('id', 'name', 'join_date', )
That has the overall effect of creating...
How to store arrays in MySQL?
...ables and JOIN them in your queries.
For example:
CREATE TABLE person (
`id` INT NOT NULL PRIMARY KEY,
`name` VARCHAR(50)
);
CREATE TABLE fruits (
`fruit_name` VARCHAR(20) NOT NULL PRIMARY KEY,
`color` VARCHAR(20),
`price` INT
);
CREATE TABLE person_fruit (
`person_id` INT NOT NULL,
`fruit_name`...
Python assigning multiple variables to same value? list behavior
...ifferent variables with equal values; they're different names for the same identical value. Variables have types, identities, addresses, and all kinds of stuff like that.
Names don't have any of that. Values do, of course, and you can have lots of names for the same value.
If you give Notorious B...
Rails has_and_belongs_to_many migration
...
You need to add a separate join table with only a restaurant_id and user_id (no primary key), in alphabetical order.
First run your migrations, then edit the generated migration file.
Rails 3
rails g migration create_restaurants_users_table
Rails 4:
rails g migration create_rest...
What does “for” attribute do in HTML tag?
...ement:
<label>Input here:
<input type='text' name='theinput' id='theinput'>
</label>
The other way is to use the for attribute, giving it the ID of the associated input:
<label for="theinput">Input here:</label>
<input type='text' name='whatever' id='theinput...