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dataframe/docs/StardustDocs/topics/updateConvert.md

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+[//]: # (title: Update / convert values)
+
+Both [`update`](update.md) and [`convert`](convert.md) can be used to change column values in a `DataFrame`.
+
+Difference between these operations:
+* `convert` allows changing the type of the column, `update` doesn't
+* `parse` is a special case of `convert` to convert String into different types automatically based on its contents
+* `unfold` is a special case of `convert` to convert `DataColumn` of objects into `ColumnGroup` based on properties of objects.
+* `update` allows filtering cells to be updated, `convert` doesn't
+* [`fill`](fill.md) is a special case of `update` to replace missing values