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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
...
SQL update fields of one table from fields of another one
...1 = a.column1,
column2 = a.column2,
column3 = a.column3
FROM a
WHERE a.id = b.id
AND b.id = 1
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How to select a single field for all documents in a MongoDB collection?
...ery. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example from the folks at Mongo, the returned documents will contain only the fields of item, qty, and _id.
Thus,...
Rails find record with zero has_many records associated [duplicate]
...overflow.com/a/5570221/417872
City.includes(:photos).where(photos: { city_id: nil })
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Possibility of duplicate Mongo ObjectId's being generated in two different collections?
Is it possible for the same exact Mongo ObjectId to be generated for a document in two different collections? I realize that it's definitely very unlikely, but is it possible?
...
Migration: Cannot add foreign key constraint
...ma::create('priorities', function($table) {
$table->increments('id', true);
$table->integer('user_id')->unsigned();
$table->string('priority_name');
$table->smallInteger('rank');
$table->text('class');
$table->timestamps('timecreat...
How to get unique device hardware id in Android? [duplicate]
How to get the unique device ID in Android which cannot be changed when performing a phone reset or OS update?
3 Answers
...
Find object by id in an array of JavaScript objects
...
Use the find() method:
myArray.find(x => x.id === '45').foo;
From MDN:
The find() method returns the first value in the array, if an element in the array satisfies the provided testing function. Otherwise undefined is returned.
If you want to find its index ...
How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
...
One-to-one: Use a foreign key to the referenced table:
student: student_id, first_name, last_name, address_id
address: address_id, address, city, zipcode, student_id # you can have a
# "link back" if you need
You must also put a unique con...
Query to list number of records in each table in a database
...ceMB
FROM
sys.tables t
INNER JOIN
sys.indexes i ON t.OBJECT_ID = i.object_id
INNER JOIN
sys.partitions p ON i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN
sys.allocation_units a ON p.partition_id = a.container_id
WHERE
t.NAME NOT LIKE 'dt%' AND
i.O...