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How to store arrays in MySQL?
...ARY KEY,
`name` VARCHAR(50)
);
CREATE TABLE fruits (
`fruit_name` VARCHAR(20) NOT NULL PRIMARY KEY,
`color` VARCHAR(20),
`price` INT
);
CREATE TABLE person_fruit (
`person_id` INT NOT NULL,
`fruit_name` VARCHAR(20) NOT NULL,
PRIMARY KEY(`person_id`, `fruit_name`)
);
The person_fruit table contai...
Install NPM into home directory with distribution nodejs package (Ubuntu)
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201
NPM will install local packages into your projects already, but I still like to keep the syste...
Deleting multiple elements from a list
... from a list at the same time? If I want to delete elements at index 0 and 2, and try something like del somelist[0] , followed by del somelist[2] , the second statement will actually delete somelist[3] .
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How do I add the contents of an iterable to a set?
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231
You can add elements of a list to a set like this:
>>> foo = set(range(0, 4))
>&g...
What does the “at” (@) symbol do in Python?
...
12 Answers
12
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How to easily truncate an array with JavaScript?
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edited May 21 '15 at 1:37
David Mason
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
... Wheel
This reduces the number of round-trips to the database from N+1 to 2.
Most ORM tools give you several ways to prevent N+1 selects.
Reference: Java Persistence with Hibernate, chapter 13.
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Convert light frequency to RGB?
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answered Sep 24 '09 at 15:47
Stephen MesaStephen Mesa
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Update multiple rows in same query using PostgreSQL
...zable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.column_b;
You can add as many columns as you like:
update test as t set
column_a = c.column_a,
column_c = c.column_c
from (values
('123...