# Constituent Elements

| Element                                                                                                                                                                                      | Definition                           |
| -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------ |
| [ColumnDefs](https://docs.pentaho.com/install/9.3-install/multidimensional-data-modeling-in-pentaho/about-multidimensional-expression-language/mondrian-schema-element-reference/columndefs) | Holder for **\<ColumnDef>** elements |
| [Rows](https://docs.pentaho.com/install/9.3-install/multidimensional-data-modeling-in-pentaho/about-multidimensional-expression-language/mondrian-schema-element-reference/rows)             | Holder for **\<Row>** elements       |