CSV¶
Plain comma-separated values. The builder treats CSV as a tabular data source — most commonly used to drive Charts rather than render features on the map.
When to use¶
- Time-series tables (date column + one or more value columns) plotted as line, area, or bar charts.
- Tabular ancillary data linked to a vector layer through a join key.
- Any one-off dataset where you want to skip GIS conversion.
Add a CSV source¶
Layer Card → Datasets → Add Dataset → Direct Connection → Data Format = CSV (Comma Separated Values).
| Field | Notes |
|---|---|
| Data Source URL | HTTPS URL ending in .csv. The first row must be the header. |
| Z-Index | Default 50. Not used for chart-only CSVs. |
The builder fetches the file when it's referenced by a chart and parses columns:
- A column whose name or values look like ISO dates is detected as the date axis.
- Numeric columns become available as Y-series.
- Other columns are exposed as labels for tooltips and filters.
See Chart CSV processing for the detection rules.
Validation¶
- The healthcheck does a HEAD request only — it does not parse the file.
- Bad delimiters or non-UTF-8 encodings are surfaced when a chart that uses the CSV is opened in the visual editor.
Tips¶
- Stick to UTF-8 with
\nline endings. Excel-exported CSVs sometimes use Windows-1252; re-save as UTF-8 if columns appear garbled. - Quote any value containing a comma; the parser doesn't try to recover from broken quoting.
- For very large CSVs (≳ 10 MB), pre-aggregate upstream — the deployed Explorer loads the whole file into memory.