[MDEV-14301] JSON_UNQUOTE returns incorrect results depending on the collation - Jira

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Bug Category:
Can result in unexpected behaviour
Release Note Summary:

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That problem is already fixed in 10.11.
Also these character set issues don't appear differently there so if not correct should be different issue.

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That problem is already fixed in 10.11. Also these character set issues don't appear differently there so if not correct should be different issue.
Sprint:
10.2.12, Q1/2026 Server Maintenance

MariaDB
MariaDB [(none)]> SELECT VERSION();
+-----------------+
\| VERSION() \|
+-----------------+
\| 10.2.10-MariaDB \|
+-----------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SET @`json` := '{"sv":"Börk"}';
Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> SELECT
-> JSON_UNQUOTE(
-> JSON_EXTRACT(CAST(@`json` AS CHAR CHARACTER SET latin1), '$.sv')
-> ) `latin1`,
-> JSON_UNQUOTE(
-> JSON_EXTRACT(CAST(@`json` AS CHAR CHARACTER SET utf8mb4), '$.sv')
-> ) `utf8mb4`;
+---------+---------+
\| latin1 \| utf8mb4 \|
+---------+---------+
\| "Börk" \| Börk \|
+---------+---------+
1 row in set (0.00 sec)

MySQL
mysql> SELECT VERSION();
+-----------+
\| VERSION() \|
+-----------+
\| 5.7.20 \|
+-----------+
1 row in set (0.00 sec)

mysql> SET @`json` := '{"sv":"Börk"}';
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT
-> JSON_UNQUOTE(
-> JSON_EXTRACT(CAST(@`json` AS CHAR CHARACTER SET latin1), '$.sv')
-> ) `latin1`,
-> JSON_UNQUOTE(
-> JSON_EXTRACT(CAST(@`json` AS CHAR CHARACTER SET utf8mb4), '$.sv')
-> ) `utf8mb4`;
+--------+---------+
\| latin1 \| utf8mb4 \|
+--------+---------+
\| Börk \| Börk \|
+--------+---------+
1 row in set (0.00 sec)

relates to

MDEV-21124 JSON_UNQUOTE fails to process surrogate pairs

MDEV-25131 using COLLATE utf8mb4_unicode_ci with GENERATED column throws error but works in mysql

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