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Sheet Editor

The sheet editor is the grid editor of the Sheet resource — a spreadsheet-like editor for CSV, JSON, and XLSX files with inline editing, data cleaning, computed columns, statistics, and an Excel-style clipboard. It is surfaced as the Data blade of a Sheet resource in the Resource Explorer (/resources/[id]/[[blade]]).

Key concepts

  • DataSource — the in-memory model of the open file: a list of Column definitions plus Row objects whose data maps column name → value. Format-specific serializers (CSV, JSON, XLSX) convert between the file bytes and this one model, so every grid feature works identically for all three formats.
  • Columns are typed — ColumnType is String, Number, Boolean, Date, or Computed. Types are inferred on import and drive cell coercion, per-column filters, statistics, and charts. Changing a column's type recasts its existing values.
  • Computed columns — read-only columns whose value is derived lazily from other columns through a transformation (math expressions, string operations, type conversion, date parts, regex extraction, dataset aggregations). See computed columns.
  • Command history — every mutation is a command object (ADataSourceCommand) pushed onto a history store, which is what powers unlimited undo/redo, including for multi-cell operations like range paste.
  • Cell selection — an Excel-style anchor/focus range selection (click, drag, Shift+click, Shift+Arrow) that keyboard copy/paste operates on. See clipboard.

The area is mature. Open work: roadmap. New ideas should be checked against deferred and rejected first.

Shipped

  • Editing — inline cell editing, add/edit/delete rows and columns, bulk select + delete, undo/redo, row drag-reorder, keyboard cell navigation, Excel-style range copy/paste (clipboard) that materializes computed-column values on copy (copy computed values).
  • Columns — reorder, visibility toggle, descriptions, type recast on change, format options (number/boolean/date), configurable footer aggregate; computed columns (Math via mathjs, ConvertTo, DatePart, RegexMatch, String, StringSplit, StringPattern, chained) and aggregation columns (average/count/min/max/rank/percent-of-total/running-sum) (computed columns).
  • Data quality — null/empty strategy, duplicate-row detection, trim/normalize strings, global find & replace.
  • Import — CSV/TSV/JSON/XLSX, import preview, paste tabular data from Excel/Sheets.
  • Export — filtered rows, column subset, JSON array, selected-rows, copy-to-clipboard (TSV).
  • Filtering & sorting — column sort, multi-column sort, per-column filters, global search, frozen row-number column.
  • Statistics & viz — per-column stats (including string/date: top value, null %), data summary footer row, outlier detection (>2σ), numeric/boolean charts, string top-10 and date monthly charts, computed-column stats.