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How to 'insert if not exists' in MySQL?
...tober 2007
To start: as of the latest MySQL, syntax presented in the title is not
possible. But there are several very easy ways to accomplish what is
expected using existing functionality.
There are 3 possible solutions: using INSERT IGNORE, REPLACE, or
INSERT … ON DUPLICATE KEY U...
Do we need type=“text/css” for in HTML5 [duplicate]
...ibute is purely advisory and explains in detail how browsers should act if it's omitted (too much to quote here). It doesn't explicitly say that an omitted type attribute is either valid or invalid, but you can safely omit it knowing that browsers will still react as you expect.
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How does MySQL process ORDER BY and LIMIT in a query?
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It will order first, then get the first 20. A database will also process anything in the WHERE clause before ORDER BY.
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Difference between a user and a schema in Oracle?
...purposes.
SCOTT is a schema that includes the EMP, DEPT and BONUS tables with various grants, and
other stuff.
SYS is a schema that includes tons of tables, views, grants, etc etc etc.
SYSTEM is a schema.....
Technically -- A schema is the set of metadata (data dictionary) used by the database,...
What are the big improvements between guava and apache equivalent libraries?
...use apache collections, string utils, etc. I need to decide if we should switch from the apache foundations implementation.
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What is the use of the square brackets [] in sql statements?
... brackets offer any advantage? When I hand code T-SQL I've never bothered with them.
9 Answers
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Using git, how do I ignore a file in one branch but have it committed in another branch?
... to Heroku . The source code tree includes a bunch of mp3 files (the website will be for a recording project I was heavily involved with).
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commands not found on zsh
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It's evident that you've managed to mess up your PATH variable. (Your current PATH doesn't contain any location where common utilities are located.)
Try:
PATH=/bin:/usr/bin:/usr/local/bin:${PATH}
export PATH
Alternativel...
Quickest way to convert XML to JSON in Java [closed]
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edited Apr 24 '19 at 18:39
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How to detect online/offline event cross-browser?
...ost, others don't.
From the spec:
Returns false if the user agent is
definitely offline (disconnected from
the network). Returns true if the user
agent might be online.
The events online and offline are
fired when the value of this attribute
changes.
The navigator.onLine attribute must
return false...