Line chart

Line charts let you visualize results from multiple queries in a single chart and apply custom settings to specific fields. This topic describes how to configure a basic line chart.

Overview

A line chart is a type of trend analysis chart. It shows how a dataset changes over a series of ordered categories, which are typically continuous time intervals. This helps you easily spot trends. With a line chart, you can clearly observe changes within a specific period, such as:

Increases or decreases
The rate of change
Patterns, such as cyclical changes
Peaks and troughs

Line charts are ideal for analyzing data trends over time. You can also plot multiple lines on the same chart to compare different datasets over the same period. This helps you analyze how the datasets interact, such as whether they increase together, decrease together, or are inversely related.

To learn how to add a line chart, see Add a chart to a dashboard.

Examples

Line chart type	Example	Related link
Basic line chart		Basic line chart
Multi-axis line chart		Configure a multi-axis line chart
Data Completion		Configure missing value replacement for a line chart

Configuration example

Basic line chart

Log on to the Simple Log Service console. In the Projects section, click the project you want.
In the left-side navigation pane, choose Dashboard > Dashboards. In the Dashboard list, click the dashboard you want. In the upper-right corner of the dashboard page, click Edit. In edit mode, choose Add > Add Chart.
In the General Configurations pane, under Chart Type, select the icon. Then, enter a query statement and click Last 15 Minutes to specify a time range.

For example, the query statement for Query A is:
```
* | select __time__,count(request_url) as pv group by __time__
```
In the right-side Query and Analysis Configurations section, set x-axis Field to __time__ and select pv for y-axis Field.

Other configurations

Configuration	Description	Example
Configure the x-axis and y-axis	Formatting the x-axis helps you view log data on a Simple Log Service dashboard within a specific time frame, such as by hour, day, week, or month. Setting thresholds on the y-axis helps you quickly identify and receive alerts for data points that are abnormal or outside the expected range. This is useful for monitoring system performance, identifying anomalies, and performing predictive analysis because you receive automatic alerts when data goes out of range. For more information, see Configure the x-axis and y-axis for a line chart.
Configure aliases and colors for a multi-axis line chart	On a multi-axis line chart, where multiple lines represent different data series, setting unique aliases and colors helps you distinguish between them. This is especially useful when a chart contains many data series. For more information, see Configure aliases and colors for a multi-axis line chart.
Configure chart type settings for a multi-axis line chart (point, line, column)	In a multi-axis line chart, you can use points, lines, and columns to represent different data: Point: Points mark specific data values, making it easy to compare exact values and their differences. Line: Lines show data trends. They display how metrics change over time or another variable, helping you understand trends and their relationships. Column: Columns are used to compare and contrast data. The height and width of columns can represent metric values, allowing for a direct visual comparison of their magnitudes and differences. For more information, see Configure chart type settings for a multi-axis line chart.

General Configurations

The General Configurations tab provides global settings for the line chart.

Basic configurations

Parameter	Description
Title	The title of the line chart.
Display Title	When you enable the Display Title switch, the title is displayed in the line chart.
Display Border	After you turn on the Show Border switch, a border is displayed in the line chart.
Display Background	When you turn on the Show Background switch, the line chart displays a background color.
Display Time	After you turn on the Show Time switch, the query time will be displayed in the line chart.
Fixed Time	After you turn on the Fixed Time switch, the time range for the query analysis is fixed and is not affected by the dashboard's global time.

Standard configurations

Parameter	Description
Format	The display format for numeric values.
Unit	The unit for numeric values.
Decimal Places	The number of decimal places to display for numeric values.
Display Name	Changes the name of the legend. If you set a display name, all legend items in the chart are renamed to this value. To modify the name of a specific legend item, use the Field Configuration tab.
Color Scheme	Select a color scheme for the chart background and legend. Built-in: Uses the default color scheme. Solid: Uses a single color that you select.

Query and analysis configurations

Parameter

Description

x-axis Field

Select a field for the x-axis.

By default, Simple Log Service automatically selects a field for the x-axis.

y-axis Field

Select one or more fields for the y-axis.

By default, Simple Log Service automatically selects fields for the y-axis.

Data configuration

Parameter	Description
Data Completion	After you enable Data Completion, Simple Log Service starts data completion from the first piece of data according to the completion window.
Completion Window	The time window for filling in missing data. The minimum value is 10 seconds. By default, Simple Log Service automatically determines the completion window.
Completion Value	The value to use for filling in missing data points. The default value is 0.

Legend configurations

Parameter	Description
Display Legend	After you turn on the Show Legend switch, the legend will be displayed in the line chart.
Legend Position	The position of the legend.
Actions	The behavior when a legend item is clicked. Single: When you click a legend item, only that item's data is displayed. Switch: Click a legend item to hide its data. Click it again to show it.
Maximum Width (Height)%	The maximum width and height of the legend.

Tooltip

Parameter	Description
Sort By	The sorting method for the data.
Display Mode	All Single
Additional Information	Adds custom information to the tooltip. You can add one item for each query. Use the `${{field}}` syntax to reference a value from the query results.

x-axis

Parameter	Description
Display x-axis	After you turn on the Show x-axis switch, the x-axis is displayed in the line chart.
x-axis Title	The title of the x-axis.
x-axis Height	The height of the x-axis. By default, Simple Log Service automatically sets the height of the x-axis.
Format	Select a format to apply to the time values on the x-axis.
Drag and Zoom	Global Single

y-axis

Parameter	Description
Display y-axis	After you turn on the Show y-axis switch, the y-axis will be displayed in the line chart.
y-axis Title	The title of the y-axis.
y-axis Position	The position of the y-axis.
Stack	If you enable this option, the y-axis data is stacked.
y-axis Width	The width of the y-axis. By default, Simple Log Service automatically sets the width of the y-axis.
Maximum Value	The maximum value for the y-axis. By default, Simple Log Service automatically sets the maximum value of the y-axis.
Minimum Value	The minimum value for the y-axis. By default, Simple Log Service automatically sets the minimum value of the y-axis.
Elastic Maximum Value	The elastic maximum value for the y-axis. This setting applies only if all y-axis values are less than this value. By default, Simple Log Service automatically sets the elastic maximum value of the y-axis.
Elastic Minimum Value	The elastic minimum value for the y-axis. This setting applies only if all y-axis values are greater than this value. By default, Simple Log Service automatically sets the elastic minimum value of the y-axis.
y-axis ID	The ID of the y-axis. This parameter is typically not needed in the General Configurations pane. If you want to define multiple y-axes, you must configure them on the Field Configuration tab. The y-axis ID can be any string. Using different IDs creates separate y-axes on the chart. For more information, see Add a line chart with multiple y-axes. The y-axis ID setting has a higher priority than the Unit setting in the Standard Configurations section. For example, if two y-axes have the same unit, they are merged into one. However, if they have the same unit but different IDs, they are displayed as two separate y-axes.

Chart configurations

Parameter	Description
Chart Type	The type of the line chart.
Connection Mode	The connection style for the lines in the chart.
Line Width	The width of the lines.
Display Point	Specifies whether to display points on the lines.
Transparency	The transparency of the line chart.
Point Size	The size of the points on the chart.
Gradient Mode	The fill gradient style for the area under the line. Transparency: The fill is based on the line color and is affected by the Transparency setting. No Gradient: No gradient is used. The area is filled with the line color.

Thresholds

Parameter	Description
Upper Boundary	Select the upper boundary line.
Lower Boundary	Select the lower boundary line.
Boundary Fill Color	The fill color.
Boundary Fill Color Opacity	The opacity of the color.

Variable substitution

Parameter	Description
Variable substitution	Variable substitution adds a variable-type filter to the chart. After configuration in General configurations, a filter appears in the upper-left corner of the chart. When you select a value, Simple Log Service replaces the variable in the query statement and reruns the analysis. Example 2: Set variable substitution.

Documentation link

Parameter	Description
Add Documentation Link	Allows you to add a custom documentation link or description. The information is displayed in the upper-right corner of the line chart.

Field Configuration

The Field Configuration tab lets you apply custom visualization settings to the results of an entire query or to a single data series within the results. For descriptions of the configuration parameters, see General Configurations.

For example, A > pv allows you to configure settings for the pv field from Query A, while B allows you to configure settings for all results from Query B. In this case, the green line represents the pv field from Query A, and the blue line represents the results from Query B. You can set the width of the green line to 6 and the blue line to 2.

On the Field Configuration tab, you can also set the Axis ID (left or right axis), Axis Position, and Unit to create a chart with dual y-axes.

Interaction events

The Interaction Occurrences tab lets you configure drill-down actions for a specific data series or for the results of an entire query. Supported actions include Open Logstore, Open Saved Search, Open Dashboard, Open Trace Analysis, Open Trace Details, and Create Custom HTTP URL. For more information, see Add interactive events to a dashboard for drill-down analysis.

For example, selecting A > pv allows you to set up an interactive event for the pv field from Query A. If you set the event to Open Logstore for the pv field, clicking any point on the green line and then clicking Open Logstore takes you to the specified Logstore.

Example: line chart styles

For more information about how to configure field colors, see Field Configuration.

* | select __time__ - __time__ % 60 as time, COUNT(*) as line1, COUNT(*) -20 as line2,   COUNT(*) - 40 as line3 GROUP BY time order by time limit 100

In the right-side Query and Analysis Configurations section, set the x-axis Field to time and select line1, line2, and line3 for the y-axis Field.