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dataframe/docs/StardustDocs/topics/schema.md

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+[//]: # (title: schema)
+
+<!---IMPORT org.jetbrains.kotlinx.dataframe.samples.api.Analyze-->
+
+Returns [`DataFrameSchema`](schemas.md) object with [`DataFrame`](DataFrame.md) schema description. It can be printed to see column structure.
+
+[`ColumnGroups`](DataColumn.md#columngroup) are marked by indentation:
+
+<!---FUN schema-->
+
+```kotlin
+df.schema()
+```
+
+<!---END-->
+
+Output:
+
+```text
+name:
+    firstName: String
+    lastName: String
+age: Int
+city: String?
+weight: Int?
+isHappy: Boolean
+```
+
+[`FrameColumns`](DataColumn.md#framecolumn) are marked with `*`:
+
+<!---FUN schemaGroupBy-->
+
+```kotlin
+df.groupBy { city }.schema()
+```
+
+<inline-frame src="resources/org.jetbrains.kotlinx.dataframe.samples.api.Analyze.schemaGroupBy.html" width="100%"/>
+<!---END-->
+
+Output:
+
+```text
+city: String?
+group: *
+    name:
+        firstName: String
+        lastName: String
+    age: Int
+    city: String?
+    weight: Int?
+    isHappy: Boolean
+```