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How do I remove a property from a JavaScript object?
...edibly in-depth blog post about the delete statement on their blog, Understanding delete. It is highly recommended.
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Can (domain name) subdomains have an underscore “_” in it?
...perfectly legal to have
an underscore in a domain name. Let me quote the standard, RFC
2181, section 11, "Name syntax":
The DNS itself places only one restriction on the particular labels
that can be used to identify resource records. That one
restriction relates to the length of the label ...
Why does NULL = NULL evaluate to false in SQL server
... in a where clause, it always evaluates to false. This is counterintuitive and has caused me many errors. I do understand the IS NULL and IS NOT NULL keywords are the correct way to do it. But why does SQL server behave this way?
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WebSockets protocol vs HTTP
There are many blogs and discussions about websocket and HTTP, and many developers and sites strongly advocate websockets, but i still can not understand why.
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Eclipse error: 'Failed to create the Java Virtual Machine'
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This will only work if the problem was not enough memory and if you lower the values in eclipse.ini. Raising them will only make this issue more probable to occur.
– Stijn de Witt
Feb 18 '13 at 14:17
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When is SQLiteOpenHelper onCreate() / onUpgrade() run?
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SQLiteOpenHelper onCreate() and onUpgrade() callbacks are invoked when the database is actually opened, for example by a call to getWritableDatabase(). The database is not opened when the database helper object itself is created.
SQLiteOpenHelper versi...
What is the difference between “AS” and “IS” in an Oracle stored procedure?
I see Oracle procedures sometimes written with "AS", and sometimes with "IS" keyword.
6 Answers
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How can I pass arguments to a batch file?
I need to pass an ID and a password to a batch file at the time of running rather than hardcoding them into the file.
17 An...
Postgres and Indexes on Foreign Keys and Primary Keys
Does Postgres automatically put indexes on Foreign Keys and Primary Keys? How can I tell? Is there a command that will return all indexes on a table?
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How I can I lazily read multiple JSON values from a file/stream in Python?
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Here's a much, much simpler solution. The secret is to try, fail, and use the information in the exception to parse correctly. The only limitation is the file must be seekable.
def stream_read_json(fn):
import json
start_pos = 0
with open(fn, 'r') as f:
while True:
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