Displaying data in bar chart from many tables

Grafana Bar Chart Panel
1

  • What Grafana version and what operating system are you using?
    v12.2

  • What are you trying to achieve?
    I’d like to see a dashboard which shows the time in minutes since last data record in every separated table. (Table name / minute)

  • How are you trying to achieve it?
    I created a variable selecting table names:
    SELECT table_name
    FROM information_schema.tables
    WHERE table_schema = ‘emspressigstrom’
    AND table_name REGEXP ‘[1]{3}’;

    multi value is off

    And a query in a bar chart:
    SELECT

    ‘${table}’ AS table_name,

    TIMESTAMPDIFF(MINUTE, MAX(Zeit), NOW()) AS delay_minutes

    FROM ${table};

    The Repeate option is selected, “table” is selected

  • What happened?
    The repeating of bar chart for each table doesn’t work, only selected table can be seen.

  • What did you expect to happen?
    A expected to see repated chart for each table

Error message if “Include All option” is selected in Variable
db query error: Error 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ‘’’ AS table_name, TIMESTAMPDIFF(MINUTE, MAX(Zeit), NOW()) AS delay_minutes…’ at line 2

  1. 0-9 ↩︎

2

What do you get when you run

SELECT table_name

FROM information_schema.tables

WHERE table_schema = ‘emspressigstrom’

AND table_name REGEXP ‘{3}’

Outside of grafana in a SQL tool for Mariadb, examine the list of tables being returned. Are they all valid table names