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Insert, on duplicate update in PostgreSQL?
...CT clause. with the following syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
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Why is it impossible to override a getter-only property and add a setter? [closed]
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Because the writer of Baseclass has explicitly declared that Bar has to be a read-only property. It doesn't make sense for derivations to break this contract and make it read-write.
I'm with Microsoft on this one.
Let's say ...
How do you append an int to a string in C++? [duplicate]
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F14
2755 bronze badges
answered Sep 25 '13 at 6:39
headmyshoulderheadmyshoulder
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Immutable vs Mutable types
I'm confused on what an immutable type is. I know the float object is considered to be immutable, with this type of example from my book:
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How important is the order of columns in indexes?
I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example:
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What is the difference between precision and scale?
What is the difference between precision and scale in Oracle? In tutorials they usually leave scale empty and set precision to 6 when creating a primary key.
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How to HTML encode/escape a string? Is there a built-in?
...cape the chars ' < ' and ' & ' as HTML entities. The less fuss the better.
8 Answers
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Passing multiple error classes to ruby's rescue clause in a DRY fashion
I have some code that needs to rescue multiple types of exceptions in ruby:
3 Answers
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Why do you need to invoke an anonymous function on the same line?
I was reading some posts about closures and saw this everywhere, but there is no clear explanation how it works - everytime I was just told to use it...:
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Can Powershell Run Commands in Parallel?
I have a powershell script to do some batch processing on a bunch of images and I'd like to do some parallel processing. Powershell seems to have some background processing options such as start-job, wait-job, etc, but the only good resource I found for doing parallel work was writing the text of a...