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MySQL ON vs USING?
...hereas ON allows a little more flexibility when the column names are not identical. However, that difference is so minor, you'd think they'd just do away with USING() .
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javascript: Clear all timeouts?
...
They are not in the window object, but they have ids, which (afaik) are consecutive integers.
So you may clear all timeouts like so:
var id = window.setTimeout(function() {}, 0);
while (id--) {
window.clearTimeout(id); // will do nothing if no timeout with id is pres...
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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unique object identifier in javascript
I need to do some experiment and I need to know some kind of unique identifier for objects in javascript, so I can see if they are the same. I don't want to use equality operators, I need something like the id() function in python.
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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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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
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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?
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