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Deleting all records in a database table
...ll.
Post.delete_all
or with a criteria
Post.delete_all "person_id = 5 AND (category = 'Something' OR category = 'Else')"
See here for more information.
The records are deleted without loading them first which makes it very fast but will break functionality like counter cache that depends on ...
List of tables, db schema, dump etc using the Python sqlite3 API
... can't find a way to get the equivalents of sqlite's interactive shell commands:
11 Answers
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Calculate distance between 2 GPS coordinates
How do I calculate distance between two GPS coordinates (using latitude and longitude)?
29 Answers
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How to send only one UDP packet with netcat?
I want to send only one short value in a UDP packet, but running the command
5 Answers
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How do I make JavaScript beep?
...directly in JavaScript. You'll need to embed a short WAV file in the HTML, and then play that via code.
An Example:
<script>
function PlaySound(soundObj) {
var sound = document.getElementById(soundObj);
sound.Play();
}
</script>
<embed src="success.wav" autostart="false" width=...
How do I find the absolute url of an action in ASP.NET MVC?
...r is the better one, this way Resharper can still validate that the Action and Controller exists. I would suggest the use of Request.Url.Scheme instead of the http, that way http and https are both supported.
– Pbirkoff
Mar 16 '12 at 10:25
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Why does C# forbid generic attribute types?
...t's not a CLI issue. The CLI spec doesn't mention it (as far as I can see) and if you use IL directly you can create a generic attribute. The part of the C# 3 spec that bans it - section 10.1.4 "Class base specification" doesn't give any justification.
The annotated ECMA C# 2 spec doesn't give any ...
MongoDB: How to query for records where field is null or not set?
...not set then:
db.emails.count({sent_at: {$exists: false}})
If its there and null, or not there at all:
db.emails.count({sent_at: null})
Refer here for querying and null
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How do I check if a SQL Server text column is empty?
I am using SQL Server 2005. I have a table with a text column and I have many rows in the table where the value of this column is not null, but it is empty. Trying to compare against '' yields this response:
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OAuth secrets in mobile apps
...cret in your data base or on the file system, but what is the best way to handle it in a mobile app (or a desktop app for that matter)?
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