Editing Splitting of articles by article ids



== Case1: Articles Numbered IDs ==
If the article number is a digit, split the article into two parts based on a remainder of 0 or 1, resulting in two nearly equal halves.

(1) Part1
<pre>
SELECT * FROM articles WHERE MOD(article_id, 2) = 0;
</pre>

(2) Part2
<pre>
SELECT * FROM articles WHERE MOD(article_id, 2) = 1;
</pre>

== Case2: Articles IDs which mix of string and number ==
If the article ID consists of numbers or text e.g. [https://en.wikipedia.org/wiki/Amazon_Standard_Identification_Number Amazon Standard Identification Number], it is divided into two parts after a formula calculation with the remainder equal to 0 or 1, resulting in two parts of different quantities. 

CONV(HEX(article_id), 16, 10) converts HEX(article_id) from hexadecimal (base 16) to decimal (base 10). Then, MOD(CONV(HEX(article_id), 16, 10), 2) computes the remainder when the converted decimal number is divided by 2.

(1) Create test data
<pre>
SET NAMES utf8mb4;

DROP TABLE IF EXISTS `strnum_article_ids`;
CREATE TABLE `strnum_article_ids` (
  `article_id` char(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
  `content` text CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_vietnamese_ci;

INSERT INTO `strnum_article_ids` (`article_id`, `content`) VALUES
('ap1p3le3',	'apple'),
('or2an3ge4',	'orange'),
('ba34na5na',	'banana'),
('wate4rle56mon',	'waterlemon'),
('ki78wi',	'kiwi');
</pre>

(2) Part 1
<pre>
SELECT *
FROM `strnum_article_ids`
WHERE MOD(CONV(HEX(article_id), 16, 10), 2) = 0;
</pre>

(3) Part 2
<pre>
SELECT *
FROM `strnum_article_ids`
WHERE MOD(CONV(HEX(article_id), 16, 10), 2) = 1;
</pre>

[[Category:Data_hygiene]]
[[Category:Data Science]]
[[Category:MySQL]]