How to view the Schema of a Table or Dataset in Power BI

How to view the Metadata of a Table or Dataset in Power Query
Scenario:
Suppose we have a sample table/dataset "tbl_Sample" in Power BI as follows:

Now we can view the Schema ( Columns definition) of a Table or Dataset using M-Query is as follows:

= Table.SelectColumns(Table.Schema(ChangeType), {"Name", "Position", "TypeName", "Kind", "IsNullable"})

Result:

let

    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("ldFRa4MwEAfw7+KzoLkk6h63sb2VllL6Ij5kXZCAS0rM9vl7sb1MN0Ynwkngl+Pyv7bNZFEXUEKZ5RkDjnWv3o3D/8ugT8E7a04jnmTW5RE3/8H8hllJGrjAetCD/jKjcfbXFbH+CtAVlmYSEutG2T7O9Oo/TYiQlSThjqwI8jRFHeGTsvjNJeXBRJJTy63Hnnqc05qo/KaA9fF8HvQcNgSrOzCFlbbBRYV154IK8UFH3eug3ga9eNQDaSGjflbeu/BTN6t6p2ghLUHAlIO9rmyhKTRIexBTvAf38Ufv7gI=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"Order Date" = _t, #"Prod ID" = _t, #"Prod Name" = _t, #"Prod Category" = _t, #"Order Qnty" = _t]),

ChangeType = Table.TransformColumnTypes(Source,{{"Order Date", type date}, {"Prod ID", Int64.Type}, {"Prod Name", type text}, {"Prod Category", type text}, {"Order Qnty", Int64.Type}}),

ViewSchema = Table.SelectColumns(Table.Schema(ChangeType), {"Name", "Position", "TypeName", "Kind", "IsNullable"})

in

    ViewSchema

I have selected only the few columns from the Schema Definition, shown below:

-----------------------------------------------------------------------------------

Suppose if we want to generate a Native SQL Select Statement from Columns of a Dataset in Power Query, we can use the following M-Query:

let

    _Table_Name = "TableName", /* Dataset Name */

    Filter_Table = Table.FirstN(Record.Field(#shared, _Table_Name), 0),

    Column_Names = Table.ColumnNames(Filter_Table),

    Source = List.Transform(Column_Names, each "[" & _ & "]"),

    Concat_Columns = "SELECT " & Text.Combine(Source, ", "),

    Query_String = Concat_Columns & " FROM [dbo]." & _Table_Name

in

    Query_String

Result:

In the above query, replace the "TableName" with the source Dataset name to generate the Native SQL Select Query.

 

Thanks, TAMATAM