Transform operations¶
Transform applies deterministic operations. Geometry is always kept. Add transformation groups them:
- Fields — Rename, Replace text, Compute column, Trim whitespace, Convert type
- Rows — Filter rows
- Geometry — Clip, Simplify, Buffer
Build them by hand, with Output Fields, from a Recipe, or — if enabled — by describing the change with AI. AI only authors the operations. Run does not call AI again.
A Transform step can instead use SQL Transform (DuckDB SQL against source). Basic operations and SQL are mutually exclusive for one step.
Operations you cannot pick in the Add dialog still exist when a Recipe, AI, or Output Fields emits them (keep_columns, drop_column).
Operations you can add¶
Rename column¶
Purpose: Rename a field.
Required: From, To
Example: shape_len → perimeter
Limits: To must be a valid identifier and must not already exist. Geometry cannot be renamed.
Replace text¶
Purpose: Find and replace inside a text field.
Required: Column, Find ( Replace may be empty to delete the find text)
Example: Rd. → Road in column name
Limits: The value is treated as text.
Trim whitespace¶
Purpose: Strip leading and trailing spaces.
Required: Column
Convert type¶
Purpose: Cast a field.
Required: Column, Target type (integer, float, or string)
Filter rows¶
Purpose: Keep rows that match a comparison.
Required (Simple): Column, Operator, Value (or Values for “is one of”)
Operators: =, !=, >, <, >=, <=, is one of, is not one of
Example: status = active
Expression mode: a condition such as population > 10000 AND status = 'active'. See Expression syntax.
Limits: No geometry column. Not a SQL query console.
Compute column¶
Purpose: Create a new field.
Required: Expression, Target column
Simple example: shape_area / 10000 into hectares
Limits (Simple): Only + - * / ( ), numbers, and existing field names. Target name must not already exist.
Expression mode: comparisons, AND / OR, and a small function list. See Expression syntax.
Clip¶
Purpose: Keep only the part of each feature inside an area. Geometries that cross the edge are cut.
Required: Bounding box (min_x, min_y, max_x, max_y) or a Polygon / MultiPolygon as WKT or GeoJSON.
Coordinates use the source CRS. GeoJibe does not assume EPSG:4326.
Simplify¶
Purpose: Reduce geometry detail.
Required: Tolerance in source CRS units. Preserve topology defaults to on.
Buffer¶
Purpose: Create an area around each feature. Points and lines become polygons.
Required: Distance in source CRS units. Optional quadrant segments under Advanced options.
Metres are only accepted when the source CRS is known to use metres. Geographic layers (for example EPSG:4326) use degrees.
Output Fields (keep / drop)¶
Unchecked names are omitted. This is how you remove columns without an extra “Remove column” card.
Internally that is keep_columns / drop_column. You will not usually add those from the Add dialog.
Geometry is never listed and cannot be dropped.
Execution order¶
Operations run in list order, then Output Fields. A later step cannot use a field you already renamed or removed.
Recipes¶
A Recipe stores operations plus Output Fields. Apply it in Transform. Save as Recipe stores the current set. Recipes are not Jobs.