# for fluentd
$ gem install fluent-plugin-mysql-query

# for td-agent
$ sudo /usr/lib64/fluent/ruby/bin/fluent-gem install fluent-plugin-mysql-query

<source>
  type            mysql_query
  host            localhost           # Optional (default: localhost)
  port            3306                # Optional (default: 3306)
  username        nagios              # Optional (default: root)
  password        passw0rd            # Optional (default nopassword)

  interval        30s                 # Optional (default: 1m)

  tag             input.mysql         # Required
  query           SHOW VARIABLES LIKE 'Thread_%' # Required
  # record hostname into message.
  record_hostname yes                 # Optional (default: no)
  # multi row results into nested record or separated message.
  nest_result     yes                 # Optional (default: no)
  nest_key        data                # Optional (default: result)
  # record the number of lines of a query result
  row_count       yes                 # Optional (default: no)
  row_count_key   row_count           # Optional (default: row_count)
</source>

<match input.mysql>
  type stdout
</match>

<source>
  type            mysql_query
  host            localhost           # Optional (default: localhost)
  port            3306                # Optional (default: 3306)
  username        nagios              # Optional (default: root)
  password        passw0rd            # Optional (default nopassword)

  cron            0 9 * * *           # Optional (run at 9 am)

  tag             input.mysql         # Required
  query           SHOW VARIABLES LIKE 'Thread_%' # Required
  # record hostname into message.
  record_hostname yes                 # Optional (default: no)
  # multi row results into nested record or separated message.
  nest_result     yes                 # Optional (default: no)
  nest_key        data                # Optional (default: result)
  # record the number of lines of a query result
  row_count       yes                 # Optional (default: no)
  row_count_key   row_count           # Optional (default: row_count)
</source>

<match input.mysql>
  type stdout
</match>

cron    * * * * *
        - – – – -
        | | | | |
        | | | | +—– Day of week (0–6) (Sunday=0) or Sun, Mon, Tue,…
        | | | +———- Month (1–12) or Jan, Feb,…
        | | +————-— Day of month (1–31)
        | +——————–— Hour (0–23)
        +————————-— Minute (0–59)

input.mysql: {"hostname":"myhost.example.com","Variable_name":"thread_cache_size","Value":"16"}
input.mysql: {"hostname":"myhost.example.com","Variable_name":"thread_stack","Value":"262144"}

input.mysql: {"hostname":"myhost.example.com","data":[{"Variable_name":"thread_cache_size","Value":"16"},{"Variable_name":"thread_stack","Value":"262144"}]}

input.mysql: {"hostname":"myhost.example.com","row_count":2,"data":[{"Variable_name":"thread_cache_size","Value":"16"},{"Variable_name":"thread_stack","Value":"262144"}]}