Type Functions Overview | Power Query M

Discover Type Functions in Power Query M Language, essential for manipulating type information. This page provides a comprehensive list and descriptions of Type Functions available in the M Language.

Function Type

Function	Description
Type.ForFunction	Returns a type that represents functions with specific parameter and return type constraints.
Type.FunctionParameters	Returns a record with field values set to the name of the parameters of a function type, and their values set to their corresponding types.
Type.FunctionRequiredParameters	Returns a number indicating the minimum number of parameters required to invoke the type of function.
Type.FunctionReturn	Returns a type returned by a function type.

Record Type

Function	Description
Type.ClosedRecord	Returns a closed version of the given record type (or the same type, if it is already closed).
Type.ForRecord	Returns a type that represents records with specific type constraints on fields.
Type.IsOpenRecord	Returns whether a record type is open.
Type.OpenRecord	Returns an opened version of the given record type (or the same type, if it is already open).
Type.RecordFields	Returns a record describing the fields of a record type with each field of the returned record type having a corresponding name and a value.

Table Type

Function	Description
Type.AddTableKey	Adds a key to the given table type.
Type.ReplaceTableKeys	Returns a new table type with all keys replaced by the specified list of keys.
Type.TableColumn	Returns the type of a column in a table.
Type.TableKeys	Returns the possibly empty list of keys for the given table type.
Type.TableRow	Returns the row type of the table type.
Type.TableSchema	Returns a table containing a description of the columns (i.e

Type Conversion and Inspection

Function	Description
Type.Facets	Returns the facets of a type.
Type.Is	Determines if a value of the first type is always compatible with the second type.
Type.IsNullable	Returns true if a type is a nullable type; otherwise, false.
Type.ListItem	Returns an item type from a list type.
Type.NonNullable	Returns the non nullable type from a type.
Type.ReplaceFacets	Replaces the facets of a type.
Type.Union	Returns the union of a list of types.

Contribute » | Contributors: Rick de Groot
Microsoft documentation: https://learn.microsoft.com/en-us/powerquery-m/type-functions