MariaDB determine json from Extended Metadata#1423
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grooverdan wants to merge 1 commit intobrianmario:masterfrom
Open
MariaDB determine json from Extended Metadata#1423grooverdan wants to merge 1 commit intobrianmario:masterfrom
grooverdan wants to merge 1 commit intobrianmario:masterfrom
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dr-m
reviewed
Feb 20, 2026
ext/mysql2/result.c
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| if (!mariadb_field_attr(&field_attr, field, | ||
| MARIADB_FIELD_ATTR_FORMAT_NAME)) { | ||
| return field_attr.length == 4 && strncmp(field_attr.str, "json", 4) == 0; |
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I think that we can rely on the short-circuit evaluation of the length, and just compare 4 bytes using memcmp, which the compiler can replace with equivalent instructions. https://godbolt.org/z/K8Wz7sn7P demonstrates that the memcmp variant would be much shorter and avoid a call to a library function.
In MariaDB the JSON of a result value is from the extended metadata of the protocol. This is returned when PROTOCOL_41 is in the connection flags. Thanks Marko Mäkelä for noting memcmp compiles to less code. ref: https://mariadb.com/docs/server/reference/clientserver-protocol/4-server-response-packets/result-set-packets#extended-metadata
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In MariaDB the JSON of a result value is from the extended metadata of the protocol.
This is returned when PROTOCOL_41 is in the connection flags.
ref: https://mariadb.com/docs/server/reference/clientserver-protocol/4-server-response-packets/result-set-packets#extended-metadata
rb_mariadb_json_typecompiles to 0 the MySQL connector as its usingmariadb_field_attrfrom MariaDB Connector/C.JSON is supported on all MariaDB supported version so I've just dropped the version check.