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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...ON DUPLICATE KEY UPDATE.
If you use INSERT IGNORE, then the row won't actually be inserted if it results in a duplicate key. But the statement won't generate an error. It generates a warning instead. These cases include:
Inserting a duplicate key in columns with PRIMARY KEY or UNIQUE constrain...
Spring DAO vs Spring ORM vs Spring JDBC
...er that this has limited usage for the following reasons:
Your should usually not catch persistence exceptions, as the provider may have rolled back the transaction (depending on the exact exception subtype), and thus you should not continue the execution with an alternative path.
The hierarchy of...
Get GPS location from the web browser
...egrated Google Maps, I need to fill the 'From' field of Google Maps dynamically.
6 Answers
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Prevent linebreak after
...y:inline;
OR
float:left;
OR
display:inline-block; -- Might not work on all browsers.
What is the purpose of using a div here? I'd suggest a span, as it is an inline-level element, whereas a div is a block-level element.
Do note that each option above will work differently.
display:inline; w...
How to delete an item in a list if it exists?
...emethod will remove only the first occurrence of thing, in order to remove all occurrences you can use while instead of if.
while thing in some_list: some_list.remove(thing)
Simple enough, probably my choice.for small lists (can't resist one-liners)
2) Duck-typed, EAFP style:
This shoot-f...
Calling pylab.savefig without display in ipython
...tion between IPython and matplotlib.pylab in this regard. But, when I call pylab.savefig("test.png") the current figure get's displayed in addition to being saved in test.png . When automating the creation of a large set of plot files, this is often undesirable. Or in the situation that an in...
How to move columns in a MySQL table?
...erform on a large table? Is it just changing some metadata, or does it actually have to reorganize data on the disk?
– Kip
Nov 12 '15 at 16:01
7
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How to create JSON string in JavaScript?
... create JSON string just to play around. It's throwing error, but if I put all the name, age, married in one single line (line 2) it doesn't. Whats the problem?
...
What is a StackOverflowError?
...
Parameters and local variables are allocated on the stack (with reference types, the object lives on the heap and a variable in the stack references that object on the heap). The stack typically lives at the upper end of your address space and as it is used up...
Put buttons at bottom of screen with LinearLayout?
...d:gravity="center|bottom"
Notice that fill_parent does not mean "take up all available space". However, if you use layout_height="0dp" with layout_weight="1", then a view will take up all available space (Can't get proper layout with "fill_parent").
Here is some code I quickly wrote up that uses ...