I'm beginner for React JS. Therefore, I want to learning how can used together React JS, Node JS and MySQL. So, Please give me some advises and example. I try do solve this problem. please help me guys.
Mysql – How to thesql database connection with react js
mysqlnode.jsreactjs
Related Solutions
You can use GROUP_CONCAT
:
SELECT person_id,
GROUP_CONCAT(hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Ludwig stated in his comment, you can add the DISTINCT
operator to avoid duplicates:
SELECT person_id,
GROUP_CONCAT(DISTINCT hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Jan stated in their comment, you can also sort the values before imploding it using ORDER BY
:
SELECT person_id,
GROUP_CONCAT(hobbies ORDER BY hobbies ASC SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Dag stated in his comment, there is a 1024 byte limit on the result. To solve this, run this query before your query:
SET group_concat_max_len = 2048;
Of course, you can change 2048
according to your needs. To calculate and assign the value:
SET group_concat_max_len = CAST(
(SELECT SUM(LENGTH(hobbies)) + COUNT(*) * LENGTH(', ')
FROM peoples_hobbies
GROUP BY person_id) AS UNSIGNED);
Data Storage:
Specify the
utf8mb4
character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4
encoding if autf8mb4_*
collation is specified (without any explicit character set).In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simply
utf8
, which only supports a subset of Unicode characters. I wish I were kidding.
Data Access:
In your application code (e.g. PHP), in whatever DB access method you use, you'll need to set the connection charset to
utf8mb4
. This way, MySQL does no conversion from its native UTF-8 when it hands data off to your application and vice versa.Some drivers provide their own mechanism for configuring the connection character set, which both updates its own internal state and informs MySQL of the encoding to be used on the connection—this is usually the preferred approach. In PHP:
If you're using the PDO abstraction layer with PHP ≥ 5.3.6, you can specify
charset
in the DSN:$dbh = new PDO('mysql:charset=utf8mb4');
If you're using mysqli, you can call
set_charset()
:$mysqli->set_charset('utf8mb4'); // object oriented style mysqli_set_charset($link, 'utf8mb4'); // procedural style
If you're stuck with plain mysql but happen to be running PHP ≥ 5.2.3, you can call
mysql_set_charset
.
If the driver does not provide its own mechanism for setting the connection character set, you may have to issue a query to tell MySQL how your application expects data on the connection to be encoded:
SET NAMES 'utf8mb4'
.The same consideration regarding
utf8mb4
/utf8
applies as above.
Output:
If your application transmits text to other systems, they will also need to be informed of the character encoding. With web applications, the browser must be informed of the encoding in which data is sent (through HTTP response headers or HTML metadata).
In PHP, you can use the
default_charset
php.ini option, or manually issue theContent-Type
MIME header yourself, which is just more work but has the same effect.When encoding the output using
json_encode()
, addJSON_UNESCAPED_UNICODE
as a second parameter.
Input:
Unfortunately, you should verify every received string as being valid UTF-8 before you try to store it or use it anywhere. PHP's
mb_check_encoding()
does the trick, but you have to use it religiously. There's really no way around this, as malicious clients can submit data in whatever encoding they want, and I haven't found a trick to get PHP to do this for you reliably.From my reading of the current HTML spec, the following sub-bullets are not necessary or even valid anymore for modern HTML. My understanding is that browsers will work with and submit data in the character set specified for the document. However, if you're targeting older versions of HTML (XHTML, HTML4, etc.), these points may still be useful:
- For HTML before HTML5 only: you want all data sent to you by browsers to be in UTF-8. Unfortunately, if you go by the only way to reliably do this is add the
accept-charset
attribute to all your<form>
tags:<form ... accept-charset="UTF-8">
. - For HTML before HTML5 only: note that the W3C HTML spec says that clients "should" default to sending forms back to the server in whatever charset the server served, but this is apparently only a recommendation, hence the need for being explicit on every single
<form>
tag.
- For HTML before HTML5 only: you want all data sent to you by browsers to be in UTF-8. Unfortunately, if you go by the only way to reliably do this is add the
Other Code Considerations:
Obviously enough, all files you'll be serving (PHP, HTML, JavaScript, etc.) should be encoded in valid UTF-8.
You need to make sure that every time you process a UTF-8 string, you do so safely. This is, unfortunately, the hard part. You'll probably want to make extensive use of PHP's
mbstring
extension.PHP's built-in string operations are not by default UTF-8 safe. There are some things you can safely do with normal PHP string operations (like concatenation), but for most things you should use the equivalent
mbstring
function.To know what you're doing (read: not mess it up), you really need to know UTF-8 and how it works on the lowest possible level. Check out any of the links from utf8.com for some good resources to learn everything you need to know.
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Best Solution
You can't add back-end activity using ReactJs.
In Nodejs is possible.
You can connect
MySql
usingsequelize ORM
in nodejs.Try this:
Setting up Sequelize MySQL connection
./app/config/env.js
./app/config/db.config.js
Create Sequelize model
Route
./app/controller/customer.route.js
Controller
Server.js