Mysql 5.7.20: Cannot create a JSON value from a string with CHARACTER SET 'binary'

问题

I am facing this issue when importing an SQL file with a table with JSON column.

The database has

Encoding: utf8mb4

Collation: utf8mb4_unicode_ci

Here's the table with the json column:

CREATE TABLE `tracking_data` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `route` varchar(191) COLLATE utf8mb4_unicode_ci NOT NULL,
  `data` json NOT NULL,
  `user_id` int(10) unsigned NOT NULL,
  `created_at` timestamp NULL DEFAULT NULL,
  `updated_at` timestamp NULL DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

I have read answers from this question on stack overflow which suggest the table must be on utf8mb4. Mine's already, but I am facing this issue still.

This is error is still thrown:

Line XXX: Cannot create a JSON value from a string with CHARACTER SET 'binary'.

When I run show session variables like 'char%';:

    Variable_name   Value 

character_set_client    utf8mb4 

character_set_connection    utf8mb4 

character_set_database  utf8mb4 

character_set_filesystem    binary 

character_set_results   utf8mb4 

character_set_server    latin1 

character_set_system    utf8 

character_sets_dir  /usr/share/mysql/charsets/

How can I fix this? Thanks!

回答1:

I can reproduce your error if my session character set is binary:

mysql [localhost] {msandbox} (test) > set names binary;
Query OK, 0 rows affected (0.00 sec)

mysql [localhost] {msandbox} (test) > insert into tracking_data (route, data, user_id) values ('route', '{"route": "value"}', 1);
ERROR 3144 (22032): Cannot create a JSON value from a string with CHARACTER SET 'binary'.

Then I can fix it by setting the session character set to match the table:

mysql [localhost] {msandbox} (test) > set names utf8mb4;
Query OK, 0 rows affected (0.00 sec)

mysql [localhost] {msandbox} (test) > insert into tracking_data (route, data, user_id) values ('route', '{"route": "value"}', 1);
Query OK, 1 row affected (0.01 sec)

So I conclude that you have set the session character set to binary.

Run show session variables like 'char%'; and see what it tells you.

回答2:

I faced the same issue today. Below were the findings for my case,

I asked one of my friend to generate an SQL dump for me to import. He used sequel-pro to generate the dump (export database). When I did the import it threw an error

Cannot create a JSON value from a string with CHARACTER SET 'binary'

So, there was an issue with the generated dump, all the json fields were converted to some raw format i.e. instead of value being

"{'key1':'value1', 'key2':'value2'}"

it was,

X'nfdsklsdsklnfjkbvkjsdbvkjhdfsbvkjdsbnvljkdsbvkjhdfbvkjdfbvjkdfb'

So, when importing the dump i.e. running the insert statements mysql could not process the data as it was not of json type.

Here is a link to the bug reported
https://github.com/sequelpro/sequelpro/issues/2397

来源：https://stackoverflow.com/questions/48526332/mysql-5-7-20-cannot-create-a-json-value-from-a-string-with-character-set-binar

标签

mysql

json

mysql-5.7