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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... using Standard SQL.
An obvious omission is the equivalent using EXCEPT:
SELECT a FROM table1
EXCEPT
SELECT a FROM table2
Note in Oracle you need to use the MINUS operator (arguably a better name):
SELECT a FROM table1
MINUS
SELECT a FROM table2
Speaking of proprietary syntax, there may also ...
Search of table names
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I'm using this and works fine
SELECT * FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME LIKE '%%'
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'any' vs 'Object'
...d to accept multiple known types, a better approach is to declare it using union types, as in
function fc(param: string|number): void {}
Obviously, OO inheritance rules still apply, so if you want to accept instances of derived classes and treat them based on their base type, as in
interface IPe...
CHECK constraint in MySQL is not working
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MySQL 8.0.16 is the first version that supports CHECK constraints.
Read https://dev.mysql.com/doc/refman/8.0/en/create-table-check-constraints.html
If you use MySQL 8.0.15 or earlier, the MySQL Reference Manual says:
T...
The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead [dupl
When I attempt to connect to a MySQL server from PHP, I see the following error:
1 Answer
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What is the MySQL VARCHAR max size?
I would like to know what the max size is for a MySQL VARCHAR type.
7 Answers
7
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Version vs build in Xcode
...ey are the same values.
When viewing the Info tab, if you right-click and select Show Raw Keys/Values, you'll see the actual names are CFBundleShortVersionString (Version) and CFBundleVersion (Build).
The Version is usually used how you appear to have been using it with Xcode 3. I'm not sure on wh...
How to change the name of a Django app?
...ete the permissions: delete from auth_permission where content_type_id in (select id from django_content_type where app_label = '<OldAppName>')
Delete content types: delete from django_content_type where app_label = '<OldAppName>'
Rename the folder of the app.
Change any references to y...
Lost connection to MySQL server at 'reading initial communication packet', system error: 0
...irewall. I use PCTools Firewall Plus and it wasn't allowing full access to MySQL. Once I changed that it was fine. Hope that helps.
Could that be it?
Also, someone here suggests that it might be because the MySQL server is bound to the loop-back IP (127.0.0.1 / localhost) which effectively cuts y...
How do I ignore all files in a folder with a Git repository in Sourcetree?
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For Sourcetree users: If you want to ignore a specific folder, just select a file from this folder, right-click on it and do "Ignore...". You will have a pop-up menu where you can ignore "Ignore everything beneath: <YOUR UNWANTED FOLDER>"
If you have the "Ignore" option greyed out...