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How important is the order of columns in indexes?
... Also keep in mind, suppose your Index is like the picture above, and your query filters on column1 and column2, but column2 is more unique and what you really want to filter on is actually column2, then its more beneficial to just have a index where column 2 is first. This may seem counte...
Rails auto-assigning id that already exists
... am guessing at your sequence name "company_id_seq", table name "company", and column name "id" ... please replace them with the correct ones. You can get the sequence name with SELECT pg_get_serial_sequence('tablename', 'columname'); or look at the table definition with \d tablename.
An alternate ...
What does the comma operator , do?
...ression2)
First expression1 is evaluated, then expression2 is evaluated, and the value of expression2 is returned for the whole expression.
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Java8 Lambdas vs Anonymous classes
Since Java8 has been recently released and its brand new lambda expressions looks to be really cool, I was wondering if this means the demise of the Anonymous classes that we were so used to.
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Resolve Type from Class Name in a Different Assembly
... answered Aug 18 '10 at 13:03
Sandor DrieënhuizenSandor Drieënhuizen
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What are inline namespaces for?
...ief, succinct example of a situation where an inline namespace is needed and where it is the most idiomatic solution?
5 A...
How to retrieve checkboxes values in jQuery
How to use jQuery to get the checked checkboxes values, and put it into a textarea immediately?
15 Answers
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Format JavaScript date as yyyy-mm-dd
...eformatting a date string should not depend on successful parsing of non-standard strings by the built-in parser. Given the OP format, it can be reformatted in less code without using a Date at all.
– RobG
Jun 16 '17 at 12:12
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Can we write our own iterator in Java?
If I have a list containing [alice, bob, abigail, charlie] and I want to write an iterator such that it iterates over elements that begin with 'a', can I write my own ? How can I do that ?
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When do you use varargs in Java?
...at("This is an integer: %d", myInt);
String.format("This is an integer: %d and a string: %s", myInt, myString);
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