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Cannot insert explicit value for identity column in table 'table' when IDENTITY_INSERT is set to OFF
... below error when I execute the following script. What is the error about, and how it can be resolved?
21 Answers
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Transaction isolation levels relation with locks on table
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I want to understand the lock each transaction isolation takes on the table
For example, you have 3 concurrent processes A, B and C. A starts a transaction, writes data and commit/rollback (depending on results). B just executes a SELECT st...
Convert a PHP object to an associative array
... )),
)
Typecasting this way will not do deep casting of the object graph and you need to apply the null bytes (as explained in the manual quote) to access any non-public attributes. So this works best when casting StdClass objects or objects with only public properties. For quick and dirty (what y...
Convert Year/Month/Day to Day of Year in Python
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A very minor and arguably pedantic addition, but using date.today() rather than datetime.now() also works and emphasizes the nature of the operation a bit more.
– Jeremy
Dec 30 '13 at 6:57
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Website screenshots
...eally want to only use php, I suggest you HTMLTOPS, which renders the page and outputs it in a ps file (ghostscript), then, convert it in a .jpg, .png, .pdf.. can be little slower with complex pages (and don't support all the CSS).
Else, you can use wkhtmltopdf to output a html page in pdf, jpg, wh...
String concatenation vs. string substitution in Python
In Python, the where and when of using string concatenation versus string substitution eludes me. As the string concatenation has seen large boosts in performance, is this (becoming more) a stylistic decision rather than a practical one?
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Should I size a textarea with CSS width / height or HTML cols / rows attributes?
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I recommend to use both. Rows and cols are required and useful if the client does not support CSS. But as a designer I overwrite them to get exactly the size I wish.
The recommended way to do it is via an external stylesheet e.g.
textarea {
widt...
Pass Method as Parameter using C#
I have several methods all with the same parameter types and return values but different names and blocks. I want to pass the name of the method to run to another method that will invoke the passed method.
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Why is a round-trip conversion via a string not safe for a double?
Recently I have had to serialize a double into text, and then get it back. The value seems to not be equivalent:
3 Answers
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Prevent any form of page refresh using jQuery/Javascript
...ens!";
}
</script>
The user will be prompted with the message, and given an option to stay on the page or continue on their way. This is becoming more common. Stack Overflow does this if you try to navigate away from a page while you are typing a post. You can't completely stop the user ...