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Insert into a MySQL table or update if exists
...) single row? Anyone else had this result? (The data is updated correctly: meaning only 1 row is updated)
– Dimitry K
Feb 20 '14 at 15:17
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Difference between Key, Primary Key, Unique Key and Index in MySQL
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KEY and INDEX are synonyms in MySQL. They mean the same thing. In databases you would use indexes to improve the speed of data retrieval. An index is typically created on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called users and y...
jQuery access input hidden value
...hidden#foo').val());
alert($('input:hidden[name=zyx]').val());
Those all mean the same thing in this example.
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Set selected option of select box
... is a very mildly edited version of Darin's demo, for an example of what I mean.
– Kenny Evitt
Aug 19 '14 at 17:51
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How to combine class and ID in CSS selector?
... are descendants of the element with an ID of header.
And #header.callout means:
Select the element which has an ID of header and also a class name of callout.
You can read more here css tricks
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What is the difference between Serializable and Externalizable in Java?
... readExternal and writeExternal methods on your class). This gives you the means to get around the reflection performance bottleneck.
In recent versions of Java (1.3 onwards, certainly) the performance of reflection is vastly better than it used to be, and so this is much less of a problem. I susp...
How to select rows with no matching entry in another table?
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@MotiKorets you mean increased the speed :)
– Ondrej Bozek
Apr 23 '19 at 14:01
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What exactly is a Maven Snapshot and why do we need it?
I am a bit confused about the meaning of a Maven Snapshot and why we build one?
13 Answers
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Android ImageView Zoom-in and Zoom-Out
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how can i zoom outside of viewpager means a whole screen?
– MD Khali
Aug 27 '18 at 13:42
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How to add a primary key to a MySQL table?
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I would definitely put FIRST after AUTO_INCREMENT, which means, that the id will be first column of the already existing table. Otherwise it will be put at the end of the table as it is written now, which can be a little confusing when doing simple SELECT * ...
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