Semantic Conventions for MariaDB

Status: Release Candidate

The Semantic Conventions for MariaDB extend and override the Database Semantic Conventions.

Spans

Spans representing calls to MariaDB adhere to the general Semantic Conventions for Database Client Spans.

db.system.name MUST be set to "mariadb" and SHOULD be provided at span creation time.

The following table outlines the span attributes applicable to MariaDB.

Attribute	Type	Description	Examples	Requirement Level	Stability
db.namespace	string	The database associated with the connection. [1]	products; customers	Conditionally Required If available without an additional network call.
db.response.status_code	string	Maria DB error code represented as a string. [2]	1008; 3058	Conditionally Required If response has ended with warning or an error.
error.type	string	Describes a class of error the operation ended with. [3]	timeout; java.net.UnknownHostException; server_certificate_invalid; 500	Conditionally Required If and only if the operation failed.
server.port	int	Server port number. [4]	80; 8080; 443	Conditionally Required [5]
db.operation.batch.size	int	The number of queries included in a batch operation. [6]	2; 3; 4	Recommended
db.query.summary	string	Low cardinality representation of a database query text. [7]	SELECT wuser_table; INSERT shipping_details SELECT orders; get user by id	Recommended [8]
db.query.text	string	The database query being executed. [9]	SELECT * FROM wuser_table where username = ?; SET mykey ?	Recommended [10]
db.response.returned_rows	int	Number of rows returned by the operation.	10; 30; 1000	Recommended
server.address	string	Name of the database host. [11]	example.com; 10.1.2.80; /tmp/my.sock	Recommended
db.operation.parameter.<key>	string	A database operation parameter, with <key> being the parameter name, and the attribute value being a string representation of the parameter value. [12]	someval; 55	Opt-In

[1] db.namespace: A connection’s currently associated database may change during its lifetime, e.g. from executing USE <database>.

If instrumentation is unable to capture the connection’s currently associated database on each query without triggering an additional query to be executed (e.g. SELECT DATABASE()), then it is RECOMMENDED to fallback and use the database provided when the connection was established.

Instrumentation SHOULD document if db.namespace reflects the database provided when the connection was established.

It is RECOMMENDED to capture the value as provided by the application without attempting to do any case normalization.

[2] db.response.status_code: MariaDB uses vendor-specific error codes on all errors and reports SQLSTATE in some cases. MariaDB error codes are more granular than SQLSTATE, so MariaDB instrumentations SHOULD set the db.response.status_code to this known error code. When SQLSTATE is available, SQLSTATE of “Class 02” or higher SHOULD be considered errors. When SQLSTATE is not available, all MariaDB error codes SHOULD be considered errors.

[3] error.type: The error.type SHOULD match the db.response.status_code returned by the database or the client library, or the canonical name of exception that occurred. When using canonical exception type name, instrumentation SHOULD do the best effort to report the most relevant type. For example, if the original exception is wrapped into a generic one, the original exception SHOULD be preferred. Instrumentations SHOULD document how error.type is populated.

[4] server.port: When observed from the client side, and when communicating through an intermediary, server.port SHOULD represent the server port behind any intermediaries, for example proxies, if it’s available.

[5] server.port: If using a port other than the default port for this DBMS and if server.address is set.

[6] db.operation.batch.size: Operations are only considered batches when they contain two or more operations, and so db.operation.batch.size SHOULD never be 1.

[7] db.query.summary: db.query.summary provides static summary of the query text. It describes a class of database queries and is useful as a grouping key, especially when analyzing telemetry for database calls involving complex queries. Summary may be available to the instrumentation through instrumentation hooks or other means. If it is not available, instrumentations that support query parsing SHOULD generate a summary following Generating query summary section.

[8] db.query.summary: if readily available or if instrumentation supports query summarization.

[9] db.query.text: For sanitization see Sanitization of db.query.text. For batch operations, if the individual operations are known to have the same query text then that query text SHOULD be used, otherwise all of the individual query texts SHOULD be concatenated with separator ; or some other database system specific separator if more applicable. Even though parameterized query text can potentially have sensitive data, by using a parameterized query the user is giving a strong signal that any sensitive data will be passed as parameter values, and the benefit to observability of capturing the static part of the query text by default outweighs the risk.

[10] db.query.text: Non-parameterized query text SHOULD NOT be collected by default unless there is sanitization that excludes sensitive data, e.g. by redacting all literal values present in the query text. See Sanitization of db.query.text. Parameterized query text SHOULD be collected by default (the query parameter values themselves are opt-in, see db.operation.parameter.<key>).

[11] server.address: When observed from the client side, and when communicating through an intermediary, server.address SHOULD represent the server address behind any intermediaries, for example proxies, if it’s available.

[12] db.operation.parameter: If a parameter has no name and instead is referenced only by index, then <key> SHOULD be the 0-based index. If db.query.text is also captured, then db.operation.parameter.<key> SHOULD match up with the parameterized placeholders present in db.query.text.

The following attributes can be important for making sampling decisions and SHOULD be provided at span creation time (if provided at all):

• db.namespace
• db.query.summary
• db.query.text
• server.address
• server.port

error.type has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used.

Value	Description	Stability
_OTHER	A fallback error value to be used when the instrumentation doesn’t define a custom value.

Metrics

MariaDB client instrumentations SHOULD collect metrics according to the general Semantic Conventions for Database Client Metrics.

db.system MUST be set to "mariadb".