Columns Input

The Columns Input is a comma-separated list of FlyQL column expressions. Each entry must reference a column declared on the source — unknown columns surface as inline diagnostics in the editor.

A single entry may include:

1. A column name (or dotted path into a JSON / Map column).
2. Zero or more transformers chained with | — they reshape the value before display.
3. An optional alias with as — the header label in the table.
4. Zero or more renderers chained with | after the alias — they control how the value is rendered (escape vs. HTML).

message
message|chars(25) as msg
labels.'app.kubernetes.io/component' as comp
payload|json as p|highlight
url as link|href("https://example.com/${value}")

See the FlyQL transformers reference and renderers reference for the full pipeline grammar.

Renderers require an alias

Renderers (highlight, hl, href) only attach after an as alias clause. Pipes before the alias are transformers, pipes after are renderers:

payload|json as p|highlight   ✓ json is a transformer, highlight is a renderer
payload|json|highlight        ✗ both treated as transformers, highlight is rejected

This is enforced by the editor — a chained renderer without an alias is flagged as a syntax error.

Nested paths (JSON, Map, Array)

For columns whose source type is JSON, JSONString, or Map (Kubernetes labels/annotations/body, ClickHouse JSON/JSONString/Map(...), etc.), use dot notation to extract nested keys:

rest.app.request.bytes
metadata.request_id
labels.'app.kubernetes.io/component'

Quote a segment with single quotes when it contains dots, slashes, or other special characters. The FlyQL nested keys docs cover the grammar in detail.

The editor will suggest discovered nested keys for JSON-typed columns as you type — driven by a sample of recent rows from the underlying datastore.

Transformers available in Telescope

Transformers are evaluated in the browser (display-side) by Telescope; not all are pushed down to SQL. The full list:

Name	Purpose
chars(from[, to])	Substring by character index.
slice(from[, to])	Substring (alias for chars with the standard slice convention).
lines(from[, to])	Slice of lines from a multi-line value.
firstline	First line of a multi-line value.
lastline	Last line of a multi-line value.
oneline	Strip newlines, collapse to a single line.
lower	Lowercase.
upper	Uppercase.
split(sep)	Split a string into an array.
join(sep)	Join an array back into a string.
json	Parse a string as JSON.
str	Coerce a value to its JSON-string representation.
type	The value’s runtime type (string, number, array, …).
fmt([lang]) / format([lang])	Pretty-print as JSON or SQL (auto-detected if lang is omitted).

lower, upper, and split are also pushed down to SQL on ClickHouse and StarRocks sources, so they can appear in query filters too. The remaining transformers are display-only — using them in a query filter raises an error.

Renderers available in Telescope

Renderers control how the post-alias value is rendered into the result cell. Telescope ships three:

Name	Purpose
highlight([lang]) / hl([lang])	Apply syntax highlighting via highlight.js — useful with `
href(template[, displayValue])	Render the cell as an <a> tag. template may include ${value}.

Only one renderer may be chained per column. Renderers do not affect query evaluation — they’re purely a display concern.

Examples

# Show only the first 80 chars of the message
message|chars(80) as msg

# Pull a tab-separated JSON payload out of a log line and render highlighted
message|split("\t")|slice(-1)|join|fmt as payload|highlight

# Link an order ID to an external system
order_id as order|href("https://orders.internal/${value}")

# Extract a specific Kubernetes label
labels.'app.kubernetes.io/component' as comp