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When and why are database joins expensive?
...s back to mitigating the size of the working set. Joins involving properly selected keys with correctly set up indexes are cheap, not expensive, because they allow significant pruning of the result before the rows are materialised.
Materialising the result involves bulk disk reads which are the mo...
How to make all Objects in AWS S3 bucket public by default?
...n.s3.amazonaws.com/policygen.html
Fill in the details such as:
In Action select "GetObject"
Select "Add Statement"
Then select "Generate Policy"
Copy the text example:
{
"Id": "Policy1397632521960",
"Statement": [
{
"Sid": "Stmt1397633323327",
"Action": [
"s3:GetObjec...
Linq style “For Each” [duplicate]
...ibe(...) seems to be around 50 times slower than ToList().ForEach(...) and Select(...).ToList()
– qujck
Jan 6 '14 at 16:44
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How to “undelete” a deleted folder in Subversion / TortoiseSVN?
... revision there your folder still exists, then right-click that folder and select "Copy to..." and enter the path there you want the folder to be re-created (probably the same path that is already in the text box).
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Git Bash doesn't see my PATH
...
While you are installing Git, you can select the option shown below, it'll help you to set the path automatically.
Its worked out for me :)
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How to change credentials for SVN repository in Eclipse?
...clipse. Another developer added an SVN repository with his credentials and selected 'Save password'. Now every time I do anything with SVN his cached credentials are used. How can I change them to mine?
...
How to import Google Web Font in CSS file?
...e (+) icon next to it. In bottom-left corner, a container titled "1 Family Selected" will appear. Click it, and it will expand. Use the "Customize" tab to select options, and then switch back to "Embed" and click "@import" under "Embed Font". Copy the CSS between the <style> tags into your sty...
Insert auto increment primary key to existing table
...etrieve it by id immediately, MySQL offers LAST_INSERT_ID() for that value SELECT * FROM table_name WHERE id = LAST_INSERT_ID() and most programming language APIs offer some function/method to return that value in the application code.
– Michael Berkowski
Jan 2...
If table exists drop table then create it, if it does not exist just create it
...up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK('__upgrade'); allows to just invoke all statements sequentially without error checking, but I don't think it's a good idea: complexity increases and locking functions in M...
SQL-Server: Error - Exclusive access could not be obtained because the database is in use
...WITH REPLACE) in optoins tab at left hand side.
Uncheck all other options.
Select source and destination database.
Click ok.
That's it.
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