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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...
What does the “at” (@) symbol do in Python?
...
12 Answers
12
Active
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What is the difference between an expression and a statement in Python?
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248
Expressions only contain identifiers, literals and operators, where operators include arithmet...
What do numbers using 0x notation mean?
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112
Literals that start with 0x are hexadecimal integers. (base 16)
The number 0x6400 is 25600.
6 ...
How to flush output of print function?
... an optional flush argument
print("Hello world!", flush=True)
On Python 2 you'll have to do
import sys
sys.stdout.flush()
after calling print. By default, print prints to sys.stdout (see the documentation for more about file objects).
...
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...
What is Func, how and when is it used
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edited Sep 2 '10 at 7:58
answered Sep 2 '10 at 7:48
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How to compare versions in Ruby?
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234
Gem::Version.new('0.4.1') > Gem::Version.new('0.10.1')
...
Annotating text on individual facet in ggplot2
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edited Aug 9 '12 at 19:24
Andy
3,8192828 silver badges2626 bronze badges
answered Aug 9 '12 a...