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Can I return the 'id' field after a LINQ insert?
When I enter an object into the DB with Linq-to-SQL can I get the id that I just inserted without making another db call? I am assuming this is pretty easy, I just don't know how.
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Get the new record primary key ID from MySQL insert query?
... a MySQL INSERT into one of my tables and the table has the column item_id which is set to autoincrement and primary key .
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Linq to Entities join vs groupjoin
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Behaviour
Suppose you have two lists:
Id Value
1 A
2 B
3 C
Id ChildValue
1 a1
1 a2
1 a3
2 b1
2 b2
When you Join the two lists on the Id field the result will be:
Value ChildValue
A a1
A a2
A a3
B b1
B b2
When you GroupJoin...
Why does Haskell's “do nothing” function, id, consume tons of memory?
Haskell has an identity function which returns the input unchanged. The definition is simple:
1 Answer
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How can I do an UPDATE statement with JOIN in SQL Server?
...f your SQL DBMS doesn't support MERGE):
ANSI/ISO:
update ud
set assid = (
select sale.assid
from sale
where sale.udid = ud.id
)
where exists (
select *
from sale
where sale.udid = ud.id
);
MySQL:
update ud u
inner join sale s on
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How can you make a custom keyboard in Android?
...it).
<?xml version="1.0" encoding="utf-8"?>
<Keyboard xmlns:android="http://schemas.android.com/apk/res/android"
android:keyWidth="15%p"
android:keyHeight="15%p" >
<Row>
<Key android:codes="1" android:keyLabel="1" android:horizontalGap="4%p"/>
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How to create a MySQL hierarchical recursive query
...: use the recursive with syntax.
For MySQL 5.x: use inline variables, path IDs, or self-joins.
MySQL 8+
with recursive cte (id, name, parent_id) as (
select id,
name,
parent_id
from products
where parent_id = 19
union all
select p.id,
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SQL Server Insert if not exists
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instead of below Code
BEGIN
INSERT INTO EmailsRecebidos (De, Assunto, Data)
VALUES (@_DE, @_ASSUNTO, @_DATA)
WHERE NOT EXISTS ( SELECT * FROM EmailsRecebidos
WHERE De = @_DE
AND Assunto = @_ASSUNTO
AND Data = @_D...
Explicitly set Id with Doctrine when using “AUTO” strategy
My entity uses this annotation for it's ID:
7 Answers
7
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Rails migration for has_and_belongs_to_many join table
...acher
for rails 3:
rails generate migration students_teachers student_id:integer teacher_id:integer
for rails < 3
script/generate migration students_teachers student_id:integer teacher_id:integer
(note the table name lists both join tables in alphabetical order)
and then for rails 3 ...