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How do I check in SQLite whether a table exists?
... the complete query is:
SELECT name FROM sqlite_master WHERE type='table' AND name='{table_name}';
Where {table_name} is the name of the table to check.
Documentation section for reference: Database File Format. 2.6. Storage Of The SQL Database Schema
This will return a list of tables with the...
MySQL maximum memory usage
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MySQL's maximum memory usage very much depends on hardware, your settings and the database itself.
Hardware
The hardware is the obvious part. The more RAM the merrier, faster disks ftw. Don't believe those monthly or weekly news letters though. MySQL doesn't scale linear - not even on Oracle hard...
What is the difference between object keys with quotes and without quotes?
...e JSON data exchange format does require double quotes around identifiers (and does not allow single quotes).
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Google Chromecast sender error if Chromecast extension is not installed or using incognito
... least, avoid requesting the extension scipt if the browser is not Chrome. And I suspect it could be possible to suppress the error even if it is Chrome, but haven't tried anything.)
If you are a user annoyed by these console messages, you can switch to Chrome if not using it already. Within Chrome...
What is a “thread” (really)?
I have been trying to find a good definition, and get an understanding, of what a thread really is.
10 Answers
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Difference between jQuery `click`, `bind`, `live`, `delegate`, `trigger` and `on` functions (with an
...list of events up in another page, the API itself is tremendously helpful, and all of what I'm discussing below is linked directly from this page.
First, .click(function) is literally a shortcut for .bind('click', function), they are equivalent. Use them when binding a handler directly to an eleme...
What is the “Execute Around” idiom?
...e Around" idiom (or similar) I've been hearing about?
Why might I use it, and why might I not want to use it?
8 Answers
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When do you use POST and when do you use GET?
...or destructive actions such as creation (I'm aware of the irony), editing, and deletion, because you can't hit a POST action in the address bar of your browser. Use GET when it's safe to allow a person to call an action. So a URL like:
http://myblog.org/admin/posts/delete/357
Should bring you to ...
What is the proper declaration of main?
... signature of the main function in C++? What is the correct return type, and what does it mean to return a value from main ? What are the allowed parameter types, and what are their meanings?
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How to create a new (and empty!) “root” branch?
...answered Oct 24 '17 at 16:57
Mr_and_Mrs_DMr_and_Mrs_D
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