Description:
When `mysqld-auto.cnf` is loaded, persisted-variable keys are taken verbatim from
the JSON file (`entry.key = it.first`). `SET PERSIST` lowercases the variable
name before storing it, and `RESET PERSIST` lowercases the requested name and
performs an exact-string match. A file written by an older server (before the
lowercasing fix) or edited by an administrator can therefore contain a
mixed-case key that can never be matched: `RESET PERSIST` returns
`ER_VAR_DOES_NOT_EXIST`, the stale entry stays in the file, and the persisted
configuration accumulates duplicate case-variant entries.
How to repeat:
```bash
IMG=mysql@sha256:85b9bf2e29cf836ecb8c2a15a935d4ba0c606631dff1dd79531a11983c638f2a
DATA=$(mktemp -d); chown 999:999 "$DATA"
docker run -d --name my57 --network none --read-only --cap-drop ALL \
--security-opt no-new-privileges=true --pids-limit 512 --memory 2048m --cpus 2 \
--user 999:999 --mount type=bind,src="$DATA",dst=/var/lib/mysql \
--tmpfs /var/run/mysqld:rw,noexec,nosuid,nodev,size=16m,uid=999,gid=999 \
-e MYSQL_ALLOW_EMPTY_PASSWORD=yes "$IMG" \
--skip-name-resolve --log-error=/var/lib/mysql/error.log --log-error-verbosity=3
# wait until ready, persist a value, then stop
docker exec my57 mysql -uroot --socket=/var/run/mysqld/mysqld.sock -e \
"SET PERSIST max_connections=222;"
docker stop my57
# simulate a legacy/hand-edited file: change only the key case
sed -i 's/"max_connections"/"Max_Connections"/' "$DATA/mysqld-auto.cnf"
cat "$DATA/mysqld-auto.cnf"
docker start my57
sleep 20
docker exec my57 mysql -uroot --socket=/var/run/mysqld/mysqld.sock -e \
"SELECT @@max_connections; RESET PERSIST max_connections;"
cat "$DATA/mysqld-auto.cnf"
docker stop my57; docker start my57; sleep 20
docker exec my57 mysql -uroot --socket=/var/run/mysqld/mysqld.sock -e \
"SELECT @@max_connections;"
```
## Actual result
The mixed-case entry is not applied (the effective value stays at the default
151), but it cannot be removed and survives every restart:
```text
mysql> SELECT @@max_connections;
151
mysql> RESET PERSIST max_connections;
ERROR 3615 (HY000): Variable max_connections does not exist in persisted config file
# mysqld-auto.cnf still contains:
{"Version": 2, "mysql_dynamic_parse_early_variables": {"Max_Connections": {"Value": "222", ...}}}
```
A subsequent `SET PERSIST max_connections=...` inserts a second, lowercase entry
instead of replacing the stale one.
## Expected result
Loading should canonicalize persisted variable names exactly like the write path
does, or the exact-match comparisons in `RESET PERSIST`/`SET PERSIST` should be
case-insensitive, so a legacy mixed-case entry can be found, updated and removed.
© 2026, Oracle Corporation and/or its affiliates
Description: When `mysqld-auto.cnf` is loaded, persisted-variable keys are taken verbatim from the JSON file (`entry.key = it.first`). `SET PERSIST` lowercases the variable name before storing it, and `RESET PERSIST` lowercases the requested name and performs an exact-string match. A file written by an older server (before the lowercasing fix) or edited by an administrator can therefore contain a mixed-case key that can never be matched: `RESET PERSIST` returns `ER_VAR_DOES_NOT_EXIST`, the stale entry stays in the file, and the persisted configuration accumulates duplicate case-variant entries. How to repeat: ```bash IMG=mysql@sha256:85b9bf2e29cf836ecb8c2a15a935d4ba0c606631dff1dd79531a11983c638f2a DATA=$(mktemp -d); chown 999:999 "$DATA" docker run -d --name my57 --network none --read-only --cap-drop ALL \ --security-opt no-new-privileges=true --pids-limit 512 --memory 2048m --cpus 2 \ --user 999:999 --mount type=bind,src="$DATA",dst=/var/lib/mysql \ --tmpfs /var/run/mysqld:rw,noexec,nosuid,nodev,size=16m,uid=999,gid=999 \ -e MYSQL_ALLOW_EMPTY_PASSWORD=yes "$IMG" \ --skip-name-resolve --log-error=/var/lib/mysql/error.log --log-error-verbosity=3 # wait until ready, persist a value, then stop docker exec my57 mysql -uroot --socket=/var/run/mysqld/mysqld.sock -e \ "SET PERSIST max_connections=222;" docker stop my57 # simulate a legacy/hand-edited file: change only the key case sed -i 's/"max_connections"/"Max_Connections"/' "$DATA/mysqld-auto.cnf" cat "$DATA/mysqld-auto.cnf" docker start my57 sleep 20 docker exec my57 mysql -uroot --socket=/var/run/mysqld/mysqld.sock -e \ "SELECT @@max_connections; RESET PERSIST max_connections;" cat "$DATA/mysqld-auto.cnf" docker stop my57; docker start my57; sleep 20 docker exec my57 mysql -uroot --socket=/var/run/mysqld/mysqld.sock -e \ "SELECT @@max_connections;" ``` ## Actual result The mixed-case entry is not applied (the effective value stays at the default 151), but it cannot be removed and survives every restart: ```text mysql> SELECT @@max_connections; 151 mysql> RESET PERSIST max_connections; ERROR 3615 (HY000): Variable max_connections does not exist in persisted config file # mysqld-auto.cnf still contains: {"Version": 2, "mysql_dynamic_parse_early_variables": {"Max_Connections": {"Value": "222", ...}}} ``` A subsequent `SET PERSIST max_connections=...` inserts a second, lowercase entry instead of replacing the stale one. ## Expected result Loading should canonicalize persisted variable names exactly like the write path does, or the exact-match comparisons in `RESET PERSIST`/`SET PERSIST` should be case-insensitive, so a legacy mixed-case entry can be found, updated and removed.