Important: This documentation is about an older version. It's relevant only to the release noted, many of the features and functions have been updated or replaced. Please view the current version.
Using MySQL in Grafana
Starting from Grafana v5.1 you can name the time column time in addition to earlier supported time_sec. Usage of time_sec will eventually be deprecated.
Grafana ships with a built-in MySQL data source plugin that allows you to query and visualize data from a MySQL compatible database.
Adding the data source
- Open the side menu by clicking the Grafana icon in the top header.
- In the side menu under the
Dashboards
link you should find a link namedData Sources
. - Click the
+ Add data source
button in the top header. - Select MySQL from the Type dropdown.
Data source options
Name | Description |
---|---|
Name | The data source name. This is how you refer to the data source in panels and queries. |
Default | Default data source means that it will be pre-selected for new panels. |
Host | The IP address/hostname and optional port of your MySQL instance. |
Database | Name of your MySQL database. |
User | Database user’s login/username |
Password | Database user’s password |
Session Timezone | Specify the time zone used in the database session, such as Europe/Berlin or +02:00 . This is necessary, if the timezone of the database (or the host of the database) is set to something other than UTC. Set the value used in the session with SET time_zone='...' . If you leave this field empty, then the time zone is not updated. For more information, refer to the MySQL documentation. |
Max open | The maximum number of open connections to the database, default unlimited (Grafana v5.4+). |
Max idle | The maximum number of connections in the idle connection pool, default 2 (Grafana v5.4+). |
Max lifetime | The maximum amount of time in seconds a connection may be reused, default 14400 /4 hours. This should always be lower than configured wait_timeout in MySQL (Grafana v5.4+). |
Min time interval
A lower limit for the $__interval and $__interval_ms variables.
Recommended to be set to write frequency, for example 1m
if your data is written every minute.
This option can also be overridden/configured in a dashboard panel under data source options. It’s important to note that this value needs to be formatted as a
number followed by a valid time identifier, e.g. 1m
(1 minute) or 30s
(30 seconds). The following time identifiers are supported:
Identifier | Description |
---|---|
y | year |
M | month |
w | week |
d | day |
h | hour |
m | minute |
s | second |
ms | millisecond |
Database User Permissions (Important!)
The database user you specify when you add the data source should only be granted SELECT permissions on
the specified database and tables you want to query. Grafana does not validate that the query is safe. The query
could include any SQL statement. For example, statements like USE otherdb;
and DROP TABLE user;
would be
executed. To protect against this we Highly recommend you create a specific mysql user with restricted permissions.
Example:
CREATE USER 'grafanaReader' IDENTIFIED BY 'password';
GRANT SELECT ON mydatabase.mytable TO 'grafanaReader';
You can use wildcards (*
) in place of database or table if you want to grant access to more databases and tables.
Query builder
The MySQL query builder is available when editing a panel using a MySQL data source. The built query can be run by pressing the Run query
button in the top right corner of the editor.
Format
The response from MySQL can be formatted as either a table or as a time series. To use the time series format one of the columns must be named time
.
Dataset and Table selection
In the dataset dropdown, choose the MySQL database to query. The dropdown is be populated with the databases that the user has access to. When the dataset is selected, the table dropdown is populated with the tables that are available.
Columns and Aggregation functions (SELECT)
Using the dropdown, select a column to include in the data. You can also specify an optional aggregation function.
Add further value columns by clicking the plus button and another column dropdown appears.
Filter data (WHERE)
To add a filter, flip the switch at the top of the editor. Using the first dropdown, select if all the filters need to match (AND) or if only one of the filters needs to match (OR).
To add more columns to filter on use the plus button.
Group By
To group the results by column, flip the group switch at the top of the editor. You can then choose which column to group the results by. The group by clause can be removed by pressing the X button.
Preview
By flipping the preview switch at the top of the editor, you can get a preview of the SQL query generated by the query builder.
Code editor
To make advanced queries, switch to the code editor by clicking code
in the top right corner of the editor. The code editor support autocompletion of tables, columns, SQL keywords, standard sql functions, Grafana template variables and Grafana macros. Columns cannot be completed before a table has been specified.
You can expand the code editor by pressing the chevron
pointing downwards in the lower right corner of the code editor.
CTRL/CMD + Return
works as a keyboard shortcut to run the query.
Macros
To simplify syntax and to allow for dynamic parts, like date range filters, the query can contain macros.
Macro example | Description |
---|---|
$__time(dateColumn) | Will be replaced by an expression to convert to a UNIX timestamp and rename the column to time_sec . For example, UNIX_TIMESTAMP(dateColumn) as time_sec |
$__timeEpoch(dateColumn) | Will be replaced by an expression to convert to a UNIX timestamp and rename the column to time_sec . For example, UNIX_TIMESTAMP(dateColumn) as time_sec |
$__timeFilter(dateColumn) | Will be replaced by a time range filter using the specified column name. For example, dateColumn BETWEEN FROM_UNIXTIME(1494410783) AND FROM_UNIXTIME(1494410983) |
$__timeFrom() | Will be replaced by the start of the currently active time selection. For example, FROM_UNIXTIME(1494410783) |
$__timeTo() | Will be replaced by the end of the currently active time selection. For example, FROM_UNIXTIME(1494410983) |
$__timeGroup(dateColumn,'5m') | Will be replaced by an expression usable in GROUP BY clause. For example, *cast(cast(UNIX_TIMESTAMP(dateColumn)/(300) as signed)*300 as signed),* |
$__timeGroup(dateColumn,'5m', 0) | Same as above but with a fill parameter so missing points in that series will be added by grafana and 0 will be used as value. |
$__timeGroup(dateColumn,'5m', NULL) | Same as above but NULL will be used as value for missing points. |
$__timeGroup(dateColumn,'5m', previous) | Same as above but the previous value in that series will be used as fill value if no value has been seen yet NULL will be used (only available in Grafana 5.3+). |
$__timeGroupAlias(dateColumn,'5m') | Will be replaced identical to $__timeGroup but with an added column alias (only available in Grafana 5.3+). |
$__unixEpochFilter(dateColumn) | Will be replaced by a time range filter using the specified column name with times represented as Unix timestamp. For example, dateColumn > 1494410783 AND dateColumn < 1494497183 |
$__unixEpochFrom() | Will be replaced by the start of the currently active time selection as Unix timestamp. For example, 1494410783 |
$__unixEpochTo() | Will be replaced by the end of the currently active time selection as Unix timestamp. For example, 1494497183 |
$__unixEpochNanoFilter(dateColumn) | Will be replaced by a time range filter using the specified column name with times represented as nanosecond timestamp. For example, dateColumn > 1494410783152415214 AND dateColumn < 1494497183142514872 |
$__unixEpochNanoFrom() | Will be replaced by the start of the currently active time selection as nanosecond timestamp. For example, 1494410783152415214 |
$__unixEpochNanoTo() | Will be replaced by the end of the currently active time selection as nanosecond timestamp. For example, 1494497183142514872 |
$__unixEpochGroup(dateColumn,'5m', [fillmode]) | Same as $__timeGroup but for times stored as Unix timestamp (only available in Grafana 5.3+). |
$__unixEpochGroupAlias(dateColumn,'5m', [fillmode]) | Same as above but also adds a column alias (only available in Grafana 5.3+). |
We plan to add many more macros. If you have suggestions for what macros you would like to see, please open an issue in our GitHub repo.
The query editor has a link named Generated SQL
that shows up after a query has been executed, while in panel edit mode. Click on it and it will expand and show the raw interpolated SQL string that was executed.
Table queries
If the Format as
query option is set to Table
then you can basically do any type of SQL query. The table panel will automatically show the results of whatever columns and rows your query returns.
Query editor with example query:
The query:
SELECT
title as 'Title',
user.login as 'Created By' ,
dashboard.created as 'Created On'
FROM dashboard
INNER JOIN user on user.id = dashboard.created_by
WHERE $__timeFilter(dashboard.created)
You can control the name of the Table panel columns by using regular as
SQL column selection syntax.
The resulting table panel:
Time series queries
If you set Format as to Time series, then the query must have a column named time that returns either a SQL datetime or any numeric datatype representing Unix epoch in seconds. In addition, result sets of time series queries must be sorted by time for panels to properly visualize the result.
A time series query result is returned in a wide data frame format. Any column except time or of type string transforms into value fields in the data frame query result. Any string column transforms into field labels in the data frame query result.
For backward compatibility, there’s an exception to the above rule for queries that return three columns including a string column named metric. Instead of transforming the metric column into field labels, it becomes the field name, and then the series name is formatted as the value of the metric column. See the example with the metric column below.
To optionally customize the default series name formatting, refer to Standard options definitions.
Example with metric
column:
SELECT
$__timeGroup(time_date_time,'5m'),
min(value_double),
'min' as metric
FROM test_data
WHERE $__timeFilter(time_date_time)
GROUP BY time
ORDER BY time
Data frame result:
+---------------------+-----------------+
| Name: time | Name: min |
| Labels: | Labels: |
| Type: []time.Time | Type: []float64 |
+---------------------+-----------------+
| 2020-01-02 03:05:00 | 3 |
| 2020-01-02 03:10:00 | 6 |
+---------------------+-----------------+
Example using the fill parameter in the $__timeGroup macro to convert null values to be zero instead:
SELECT
$__timeGroup(createdAt,'5m',0),
sum(value_double) as value,
hostname
FROM test_data
WHERE
$__timeFilter(createdAt)
GROUP BY time, hostname
ORDER BY time
Given the data frame result in the following example and using the graph panel, you will get two series named value 10.0.1.1 and value 10.0.1.2. To render the series with a name of 10.0.1.1 and 10.0.1.2 , use a [Standard options definitions display value of ${__field.labels.hostname}
.
Data frame result:
+---------------------+---------------------------+---------------------------+
| Name: time | Name: value | Name: value |
| Labels: | Labels: hostname=10.0.1.1 | Labels: hostname=10.0.1.2 |
| Type: []time.Time | Type: []float64 | Type: []float64 |
+---------------------+---------------------------+---------------------------+
| 2020-01-02 03:05:00 | 3 | 4 |
| 2020-01-02 03:10:00 | 6 | 7 |
+---------------------+---------------------------+---------------------------+
Example with multiple columns:
SELECT
$__timeGroup(time_date_time,'5m'),
min(value_double) as min_value,
max(value_double) as max_value
FROM test_data
WHERE $__timeFilter(time_date_time)
GROUP BY time
ORDER BY time
Data frame result:
+---------------------+-----------------+-----------------+
| Name: time | Name: min_value | Name: max_value |
| Labels: | Labels: | Labels: |
| Type: []time.Time | Type: []float64 | Type: []float64 |
+---------------------+-----------------+-----------------+
| 2020-01-02 03:04:00 | 3 | 4 |
| 2020-01-02 03:05:00 | 6 | 7 |
+---------------------+-----------------+-----------------+
Currently, there is no support for a dynamic group by time based on time range and panel width. This is something we plan to add.
Templating
This feature is currently available in the nightly builds and will be included in the 5.0.0 release.
Instead of hard-coding things like server, application and sensor name in your metric queries you can use variables in their place. Variables are shown as dropdown select boxes at the top of the dashboard. These dropdowns make it easy to change the data being displayed in your dashboard.
Check out the Templating documentation for an introduction to the templating feature and the different types of template variables.
Query Variable
If you add a template variable of the type Query
, you can write a MySQL query that can
return things like measurement names, key names or key values that are shown as a dropdown select box.
For example, you can have a variable that contains all values for the hostname
column in a table if you specify a query like this in the templating variable Query setting.
SELECT hostname FROM my_host
A query can return multiple columns and Grafana will automatically create a list from them. For example, the query below will return a list with values from hostname
and hostname2
.
SELECT my_host.hostname, my_other_host.hostname2 FROM my_host JOIN my_other_host ON my_host.city = my_other_host.city
To use time range dependent macros like $__timeFilter(column)
in your query the refresh mode of the template variable needs to be set to On Time Range Change.
SELECT event_name FROM event_log WHERE $__timeFilter(time_column)
Another option is a query that can create a key/value variable. The query should return two columns that are named __text
and __value
. The __text
column value should be unique (if it is not unique then the first value is used). The options in the dropdown will have a text and value that allows you to have a friendly name as text and an id as the value. An example query with hostname
as the text and id
as the value:
SELECT hostname AS __text, id AS __value FROM my_host
You can also create nested variables. For example if you had another variable named region
. Then you could have
the hosts variable only show hosts from the current selected region with a query like this (if region
is a multi-value variable then use the IN
comparison operator rather than =
to match against multiple values):
SELECT hostname FROM my_host WHERE region IN($region)
Using __searchFilter
to filter results in Query Variable
Available from Grafana 6.5 and above
Using __searchFilter
in the query field will filter the query result based on what the user types in the dropdown select box.
When nothing has been entered by the user the default value for __searchFilter
is %
.
Important that you surround the
__searchFilter
expression with quotes as Grafana does not do this for you.
The example below shows how to use __searchFilter
as part of the query field to enable searching for hostname
while the user types in the dropdown select box.
Query
SELECT hostname FROM my_host WHERE hostname LIKE '$__searchFilter'
Using Variables in Queries
From Grafana 4.3.0 to 4.6.0, template variables are always quoted automatically so if it is a string value do not wrap them in quotes in where clauses.
From Grafana 4.7.0, template variable values are only quoted when the template variable is a multi-value
.
If the variable is a multi-value variable then use the IN
comparison operator rather than =
to match against multiple values.
There are two syntaxes:
$<varname>
Example with a template variable named hostname
:
SELECT
UNIX_TIMESTAMP(atimestamp) as time,
aint as value,
avarchar as metric
FROM my_table
WHERE $__timeFilter(atimestamp) and hostname in($hostname)
ORDER BY atimestamp ASC
[[varname]]
Example with a template variable named hostname
:
SELECT
UNIX_TIMESTAMP(atimestamp) as time,
aint as value,
avarchar as metric
FROM my_table
WHERE $__timeFilter(atimestamp) and hostname in([[hostname]])
ORDER BY atimestamp ASC
Disabling Quoting for Multi-value Variables
Grafana automatically creates a quoted, comma-separated string for multi-value variables. For example: if server01
and server02
are selected then it will be formatted as: 'server01', 'server02'
. Do disable quoting, use the csv formatting option for variables:
${servers:csv}
Read more about variable formatting options in the Variables documentation.
Annotations
Annotations allow you to overlay rich event information on top of graphs. You add annotation queries via the Dashboard menu / Annotations view.
Example query using time column with epoch values:
SELECT
epoch_time as time,
metric1 as text,
CONCAT(tag1, ',', tag2) as tags
FROM
public.test_data
WHERE
$__unixEpochFilter(epoch_time)
Example region query using time and timeend columns with epoch values:
Only available in Grafana v6.6+.
SELECT
epoch_time as time,
epoch_timeend as timeend,
metric1 as text,
CONCAT(tag1, ',', tag2) as tags
FROM
public.test_data
WHERE
$__unixEpochFilter(epoch_time)
Example query using time column of native SQL date/time data type:
SELECT
native_date_time as time,
metric1 as text,
CONCAT(tag1, ',', tag2) as tags
FROM
public.test_data
WHERE
$__timeFilter(native_date_time)
Name | Description |
---|---|
time | The name of the date/time field. Could be a column with a native SQL date/time data type or epoch value. |
timeend | Optional name of the end date/time field. Could be a column with a native SQL date/time data type or epoch value. (Grafana v6.6+) |
text | Event description field. |
tags | Optional field name to use for event tags as a comma separated string. |
Alerting
Time series queries should work in alerting conditions. Table formatted queries are not yet supported in alert rule conditions.
Configure the data source with provisioning
It’s now possible to configure data sources using config files with Grafana’s provisioning system. You can read more about how it works and all the settings you can set for data sources on the provisioning docs page
Here are some provisioning examples for this data source.
apiVersion: 1
datasources:
- name: MySQL
type: mysql
url: localhost:3306
database: grafana
user: grafana
jsonData:
maxOpenConns: 0 # Grafana v5.4+
maxIdleConns: 2 # Grafana v5.4+
connMaxLifetime: 14400 # Grafana v5.4+
secureJsonData:
password: ${GRAFANA_MYSQL_PASSWORD}