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What is the difference between SqlCommand.CommandTimeout and SqlConnection.ConnectionTimeout?
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Yes. CommandTimeout is how long a single command can take to complete. ConnectionTimeout is how long it can take to establish a connection to the server to start with.
For instance, you may be executing relatively long-running queries - it's perfectly okay for them to take 10 minut...
How do ACID and database transactions work?
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ACID is a set of properties that you would like to apply when modifying a database.
Atomicity
Consistency
Isolation
Durability
A transaction is a set of related changes which is used to achieve some of the ACID properties. Transactions are tools to achieve the ACID pro...
Rails 2.3-style plugins and deprecation warnings running task in Heroku
I'm upgrading to Rails 3.2, and running rake db:migrate gives me several errors of the form:
8 Answers
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Need for predictable random generator
... got a problem with random numbers. Let's say that a player has 20% chance to get a critical hit with his sword. That means, 1 out of 5 hits should be critical. The problem is I got very bad real life results — sometimes players get 3 crits in 5 hits, sometimes none in 15 hits. Battles are rather ...
memory_get_peak_usage() with “real usage”
If the real_usage argument is set to true the PHP DOCS say it will get the real size of memory allocated from system. If it's false it will get the memory reported by emalloc()
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JSLint says “missing radix parameter”
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It always a good practice to pass radix with parseInt -
parseInt(string, radix)
For decimal -
parseInt(id.substring(id.length - 1), 10)
If the radix parameter is omitted, JavaScript assumes the following:
If the string begins with "0x", the radix i...
Interop type cannot be embedded
...llows primary interop assemblies (or rather, the bits of it that you need) to be embedded into your assembly so that you don't need to deploy them alongside your application.
For whatever reason, this assembly can't be embedded - but it sounds like that's not a problem for you. Just open the Proper...
Can't import my own modules in Python
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In your particular case it looks like you're trying to import SomeObject from the myapp.py and TestCase.py scripts. From myapp.py, do
import SomeObject
since it is in the same folder. For TestCase.py, do
from ..myapp import SomeObject
However, this will work only if you ...
embedding image in html email
I'm trying to send a multipart/related html email with embedded gif images. This email is generated using Oracle PL/SQL. My attempts have failed, with the image showing up as a red X (in Outlook 2007 and yahoo mail)
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Adding placeholder text to textbox
I am looking for a way to add placeholder text to a textbox like you can with a textbox in html5.
24 Answers
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