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What requests do browsers' “F5” and “Ctrl + F5” refreshes generate?
...trol by adding "Pragma: No-cache" when you pressed CTRL-F5.
Edit: Updated table
The table below is updated with information on what will happen when the browser's refresh-button is clicked (after a request by Joel Coehoorn), and the "max-age=0" Cache-control-header.
Updated table, 27 September 20...
Why is SELECT * considered harmful?
...work. This is especially true when someone adds new columns to underlying tables that didn't exist and weren't needed when the original consumers coded their data access.
Indexing issues. Consider a scenario where you want to tune a query to a high level of performance. If you were to use *, and ...
How to export table as CSV with headings on Postgresql?
I'm trying to export a PostgreSQL table with headings to a CSV file via command line, however I get it to export to CSV file, but without headings.
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How do I use CREATE OR REPLACE?
... post for the third time, I'll reformulate this:
This does not work on tables :)
And yes, there is documentation on this syntax, and there are no REPLACE option for CREATE TABLE.
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Is a one column table good design? [closed]
It it ok to have a table with just one column? I know it isn't technically illegal, but is it considered poor design?
15 A...
Rename a table in MySQL
Renaming a table is not working in MySQL
16 Answers
16
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The ALTER TABLE statement conflicted with the FOREIGN KEY constraint
I have a problem when trying to add a foreign key to my tblDomare table; what am I doing wrong here?
18 Answers
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Android Studio: how to attach Android SDK sources?
...for SDK is available only for API levels 14 and above.
UPDATE ( Based on stable release 3.2.1):
Google changes the approach of shipping the sources, so lets see what changed.
Go to the following location
Preferences -> Apperance & Behaviour -> System Settings -> Android SDK
Quite ...
What's the difference between TRUNCATE and DELETE in SQL
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General Overview
If you want to quickly delete all of the rows from a table, and you're really sure that you want to do it, and you do not have foreign keys against the tables, then a TRUNCATE is probably going to be faster than a DELETE.
Various system-specific issues have to be considered, a...
How do HashTables deal with collisions?
I've heard in my degree classes that a HashTable will place a new entry into the 'next available' bucket if the new Key entry collides with another.
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