Cell Types Reference

Notebooks support 11 cell types. Each cell has a name (unique within the notebook), a type, and a layout controlling its display height and collapsed state.

Data cells (table, chart, log, etc.) execute SQL queries and register their results in the local WASM query engine, making them available for downstream cells to query.

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Markdown

Static text and documentation using GitHub Flavored Markdown.

Configuration:

Field	Type	Description
content	string	Markdown text to render

Features:

• Full GitHub Flavored Markdown: headings, tables, lists, code blocks, strikethrough
• Supports variable substitution: $variable, $variable.column, $begin, $end
• Validates macro references during editing — warns about undefined variables
• Does not execute queries or block downstream cells

Example content:

# Dashboard for $process_id

Showing data from **$begin** to **$end**.

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Variable

User-configurable inputs that populate $variable references in downstream cells. Variable cells render in the cell title bar rather than taking up vertical space.

There are four variable subtypes, controlled by the variableType field.

Common configuration:

Field	Type	Description
variableType	'text' | 'combobox' | 'expression' | 'datasource'	Variable subtype
defaultValue	string or object	Default value used when no URL override is present
dataSource	string	Data source for SQL queries (combobox only)

See Variables for full documentation of the variable system including scope, expressions, and URL sync.

Text

Free-form text input. The user types a value directly. No SQL execution.

variableType: 'text'
defaultValue: 'cpu_usage'

Combobox

Dropdown populated by a SQL query. Single-column queries produce simple string options. Multi-column queries produce options with named fields accessible via $variable.column syntax.

Field	Type	Description
sql	string	SQL query returning option values
dataSource	string	Data source for the query

-- Single column: options are strings
SELECT DISTINCT name FROM measures

-- Multi-column: options are objects with .name and .unit fields
SELECT DISTINCT name, unit FROM measures

After execution, the current value is validated against available options. If invalid, the default value or first option is auto-selected.

Expression

Computed value from a JavaScript expression. Evaluated automatically — not user-editable at runtime.

Field	Type	Description
expression	string	JavaScript expression to evaluate

Available bindings: $begin, $end, $duration_ms, $innerWidth, $devicePixelRatio, and upstream variables as $variableName.

Available functions: snap_interval(), Math.*.

// Compute a time bin interval based on viewport width
snap_interval($duration_ms / $innerWidth)

See Expression Evaluation for details.

Datasource

Dropdown populated with available data sources from the API. Use with $variableName in a query cell's data source field to route queries to user-selected backends.

variableType: 'datasource'
defaultValue: 'production'

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Table

SQL query results displayed in a sortable, paginated table.

Configuration:

Field	Type	Description
sql	string	SQL query with macro substitution
dataSource	string	Data source override

Options:

Field	Type	Description
sortColumn	string	Currently sorted column
sortDirection	'asc' | 'desc'	Sort direction
pageSize	number	Rows per page (default: 50)
hiddenColumns	string[]	Columns to hide
overrides	array	Column format overrides

Features:

• Sticky header with click-to-sort columns
• Column hiding via context menu, with a restoration bar to unhide
• Client-side pagination with configurable page size
• Sort column available as $order_by macro in SQL for server-side sorting
• Column format overrides with markdown and row macros ($row.columnName)
• Results registered in the local WASM query engine under the cell name for downstream queries

Column format overrides:

Override how a column renders by providing a markdown format string with row macros:

[$row.exe](/process/$row.process_id?from=$begin&to=$end)

This renders the exe column as a link to the process page.

Example SQL:

SELECT process_id, exe, start_time, username, computer
FROM processes
ORDER BY $order_by
LIMIT 100

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Transposed Table

SQL results with rows and columns swapped. The original column names become the first column, and each result row becomes a subsequent column. Useful for displaying metadata or key-value properties.

Configuration:

Same as Table — sql, dataSource, and options for hidden rows, page size, and format overrides.

Options:

Field	Type	Description
pageSize	number	Page size for scrolling
hiddenRows	string[]	Hidden row names (original column names)
overrides	array	Row rendering overrides

Features:

• Row hiding via right-click context menu, with a restoration bar to unhide
• Row format overrides with markdown and row macros (same syntax as table column overrides)
• Results registered in the local WASM query engine under the cell name for downstream queries

Example:

A query returning process_id, exe, username, computer for a single row displays as:

Field	Value
process_id	abc-123
exe	my-service
username	admin
computer	prod-01

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Chart

Multi-query time-series charts supporting line and bar chart types.

Configuration:

Field	Type	Description
queries	array	One or more query definitions
options.scale_mode	'p99' | 'max'	Y-axis scaling mode
options.chart_type	'line' | 'bar'	Chart type

Query definition:

Field	Type	Description
sql	string	SQL query returning time + value columns
name	string	Query name (used for WASM table registration)
unit	string	Y-axis unit label
label	string	Series label override
dataSource	string	Per-query data source

Scale modes:

• p99 (default) — scales Y-axis to the 99th percentile, handling outliers gracefully
• max — scales Y-axis from 0 to the maximum value

Features:

• Multiple queries per chart, each with its own data source and unit
• Color-coded series with a rotating palette
• Drag-to-zoom: drag horizontally on the chart to select a time range and zoom in
• Chart type and scale mode toggleable via controls
• Each query's results are registered in the WASM engine as cellName.queryName

Example:

SELECT time, value
FROM measures
WHERE name = '$metric'
ORDER BY time

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Log

SQL query results formatted as log entries with level-based coloring.

Configuration:

Field	Type	Description
sql	string	SQL query returning log data
dataSource	string	Data source override

Options:

Field	Type	Description
pageSize	number	Entries per page (default: 50)

Expected columns:

The renderer auto-classifies columns by name:

• time — event timestamp
• level — log level (ERROR, WARN, INFO, DEBUG, TRACE)
• target — logger target/module
• msg — log message

Additional columns are rendered as fixed-width monospace text.

• Results registered in the local WASM query engine under the cell name for downstream queries

Level coloring:

Level	Color
ERROR	Red
WARN	Yellow
INFO	Gray
DEBUG/TRACE	Muted

Example SQL:

SELECT time, level, target, msg
FROM log_entries
ORDER BY time DESC
LIMIT 500

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Property Timeline

Visualizes how JSON properties change over time as horizontal timeline segments.

Configuration:

Field	Type	Description
sql	string	SQL query returning time and properties (JSON) columns
dataSource	string	Data source override

Options:

Field	Type	Description
selectedKeys	string[]	Property keys to display as timeline tracks

Features:

• Parses JSON properties from each row and detects value changes
• Each selected property key displays as a horizontal timeline track
• Interactive key selection — add or remove property keys from the display
• Time range zoom via drag selection
• Fills time gaps with "no value" state
• Results registered in the local WASM query engine under the cell name for downstream queries

Expected columns:

• time — timestamp
• properties — JSON object string (e.g., {"cpu": 45, "state": "running"})

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Swimlane

Horizontal lane visualization for thread or async activity over time. Each lane shows one or more time segments as horizontal bars.

Configuration:

Field	Type	Description
sql	string	SQL query returning lane data
dataSource	string	Data source override

Required columns:

Column	Type	Description
id	string	Unique lane identifier
name	string	Lane display name
begin	timestamp	Segment start time
end	timestamp	Segment end time

Multiple rows with the same id create multiple segments in one lane. Lanes are ordered by first occurrence in the query results.

Features:

• Fixed label column on the left with lane names
• Horizontal time bars in the center
• Drag-to-zoom time selection
• Time axis with formatted tick marks
• Results registered in the local WASM query engine under the cell name for downstream queries

Example SQL:

SELECT
  arrow_cast(stream_id, 'Utf8') as id,
  concat(
    arrow_cast(property_get("streams.properties", 'thread-name'), 'Utf8'),
    '-',
    arrow_cast(property_get("streams.properties", 'thread-id'), 'Utf8')
  ) as name,
  begin_time as begin,
  end_time as end
FROM blocks
WHERE process_id = '$process_id'
  AND array_has("streams.tags", 'cpu')
ORDER BY name, begin

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Perfetto Export

Exports trace data to Perfetto UI for visualization, or downloads it as a file.

Configuration:

Field	Type	Description
processIdVar	string	Variable name containing the process ID (default: $process_id)
spanType	'thread' | 'async' | 'both'	Which span types to include (default: both)
dataSource	string	Data source override

Features:

• Split button: Open in Perfetto (primary) or Download (secondary)
• Shows a warning if the referenced variable is empty or undefined
• Caches the generated trace buffer — cleared when process ID, span type, time range, or data source changes
• Progress indicator during trace generation
• No automatic execution — triggered by user button click

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Reference Table

Embeds inline CSV data that is registered as a queryable table in the local WASM query engine. Downstream cells can query it by the cell's name.

Configuration:

Field	Type	Description
csv	string	CSV data with headers in the first row

Options:

Same as Table — sortColumn, sortDirection, pageSize, hiddenColumns.

Features:

• CSV is parsed into an Arrow table with automatic type inference (numeric, boolean, string)
• Registered in the WASM engine under the cell name — queryable by downstream cells
• Displays as a sortable, paginated table (same UI as the Table cell)
• Useful for lookup tables, configuration data, or reference values

Example:

A cell named thresholds with this CSV:

metric,warn_threshold,error_threshold
cpu_usage,80,95
memory_usage,70,90
disk_usage,85,95

Can be queried by a downstream table cell:

SELECT m.name, m.value, t.warn_threshold, t.error_threshold
FROM raw_metrics m
JOIN thresholds t ON m.name = t.metric
WHERE m.value > t.warn_threshold

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Horizontal Group (HG)

A container cell that arranges its children side by side in a horizontal layout.

Configuration:

Field	Type	Description
children	array	Child cell configurations (any type except HG)

Features:

• Children render side by side with equal width
• Drag children horizontally to reorder within the group
• Drag a child vertically (out of the group area) to extract it to the main cell list
• Add new children via the group editor
• Each child has independent execution, state, and data source settings
• Aggregate stats (row count, byte size) displayed in the group header

Constraints:

• HG cells cannot be nested — no HG inside another HG
• During execution, children are flattened into the main sequence and execute left to right
• Variables defined in child cells are visible to cells below the group

Example use case:

Place two related charts side by side — one showing CPU usage and another showing memory usage — for a compact comparison view.