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How do I search for an object by its ObjectId in the mongo console?
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Not strange at all, people do this all the time. Make sure the collection name is correct (case matters) and that the ObjectId is exact.
Documentation is here
> db.test.insert({x: 1})
> db.test.find() ...
How do I use prepared statements in SQlite in Android?
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I use prepared statements in Android all the time, it's quite simple :
SQLiteDatabase db = dbHelper.getWritableDatabase();
SQLiteStatement stmt = db.compileStatement("INSERT INTO Country (code) VALUES (?)");
stmt.bindString(1, "US");
stmt.executeInsert();
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capturing self strongly in this block is likely to lead to a retain cycle
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Good answer, but I take small issue with you saying: “you can't refer to self or properties on self from within a block that will be strongly retained by self.” This is not strictly true. Please see my answer below. Better to say, “you must take...
How do I execute inserts and updates in an Alembic upgrade script?
...s is useful for simple migrations.
Use the models and session as you normally would in your application.
"""create teams table
Revision ID: 169ad57156f0
Revises: 29b4c2bfce6d
Create Date: 2014-06-25 09:00:06.784170
"""
revision = '169ad57156f0'
down_revision = '29b4c2bfce6d'
from alembic imp...
Git - How to use .netrc file on Windows to save user and password
...to 'C:\Users\"username"'.
Go that that folder (cd %HOME%) and make a file called '_netrc'
Note: Again, for Windows, you need a '_netrc' file, not a '.netrc' file.
Its content is quite standard (Replace the <examples> with your values):
machine <hostname1>
login <login1>
password...
Save classifier to disk in scikit-learn
... Works like a charm! I was trying to use np.savez and load it back all along and that never helped. Thanks a lot.
– Kartos
Jan 29 '14 at 9:29
10
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Difference between dispatch_async and dispatch_sync on serial queue?
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I do mean serial execution. In point of view that all tasks are executed serial regards to other tasks in the same queue. Of cause it still can be concurrent regards to other queues. It is the whole point of GCD that tasks can be dispatched and executed concurrently.
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How do I do base64 encoding on iOS?
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A really, really fast implementation which was ported (and modified/improved) from the PHP Core library into native Objective-C code is available in the QSStrings Class from the QSUtilities Library. I did a quick benchmark: a 5....
How to do date/time comparison
...Go? I have to sort data based on date and time - independently. So I might allow an object that occurs within a range of dates so long as it also occurs within a range of times. In this model, I could not simply just select the oldest date, youngest time/latest date, latest time and Unix() seconds c...
Does C++ support 'finally' blocks? (And what's this 'RAII' I keep hearing about?)
Does C++ support ' finally ' blocks?
16 Answers
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