fix: Add mariadb_dialect to address the MariaDB differences in INNODB_METRICS

plugins/inputs/mysql/README.md

@@ -281,7 +281,8 @@ and process. It has following fields:
 for them. It has following fields:
   * auto_increment_column(int, number)
   * auto_increment_column_max(int, number)
-* InnoDB metrics - all metrics of information_schema.INNODB_METRICS with a status "enabled"
+* InnoDB metrics - all metrics of information_schema.INNODB_METRICS with a status "enabled". For MariaDB,
+`mariadb_dialect = true` to use `ENABLED=1`.
 * Perf table lock waits - gathers total number and time for SQL and external
 lock waits events for each table and operation. It has following fields.
 The unit of fields varies by the tags.

plugins/inputs/mysql/mysql.go

@@ -231,6 +231,13 @@ const (
         FROM information_schema.INNODB_METRICS
         WHERE status='enabled'
     `
+	innoDBMetricsQueryMariadb = `
+        EXECUTE IMMEDIATE CONCAT("
+            SELECT NAME, COUNT
+            FROM information_schema.INNODB_METRICS
+            WHERE ", IF(version() REGEXP '10\.[1-4].*',"status='enabled'", "ENABLED=1"), "
+        ");
+	`
 	perfTableIOWaitsQuery = `
         SELECT OBJECT_SCHEMA, OBJECT_NAME, COUNT_FETCH, COUNT_INSERT, COUNT_UPDATE, COUNT_DELETE,
         SUM_TIMER_FETCH, SUM_TIMER_INSERT, SUM_TIMER_UPDATE, SUM_TIMER_DELETE
@@ -1245,8 +1252,18 @@ func (m *Mysql) gatherInfoSchemaAutoIncStatuses(db *sql.DB, serv string, acc tel
 // gatherInnoDBMetrics can be used to fetch enabled metrics from
 // information_schema.INNODB_METRICS
 func (m *Mysql) gatherInnoDBMetrics(db *sql.DB, serv string, acc telegraf.Accumulator) error {
+	var (
+		query string
+	)
+
+	if m.MariadbDialect {
+		query = innoDBMetricsQueryMariadb
+	} else {
+		query = innoDBMetricsQuery
+	}
+
 	// run query
-	rows, err := db.Query(innoDBMetricsQuery)
+	rows, err := db.Query(query)
 	if err != nil {
 		return err
 	}