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Query groupBy multiple columns (SqlDataConnection type provider)

Querying a players table grouped by first, then by the last name and counting the number of occurrence

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query {
    for row in Players do
    let key = AnonymousObject<_,_>(row.NameFirst, row.NameLast)
    groupValBy row key into grouping
    select (grouping.Key.Item1, grouping.Key.Item2, grouping.Count())
} |> Seq.iter (fun row -> printfn "%A" row)
val query : Linq.QueryBuilder

Full name: Microsoft.FSharp.Core.ExtraTopLevelOperators.query
val row : obj
val key : obj
custom operation: groupValBy ('Value) ('Key)

Calls Linq.QueryBuilder.GroupValBy
val grouping : System.Linq.IGrouping<obj,obj>
custom operation: select ('Result)

Calls Linq.QueryBuilder.Select
property System.Linq.IGrouping.Key: obj
module Seq

from Microsoft.FSharp.Collections
val iter : action:('T -> unit) -> source:seq<'T> -> unit

Full name: Microsoft.FSharp.Collections.Seq.iter
val row : obj * obj * obj
val printfn : format:Printf.TextWriterFormat<'T> -> 'T

Full name: Microsoft.FSharp.Core.ExtraTopLevelOperators.printfn
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More information

Link:http://fssnip.net/lc
Posted:5 years ago
Author:-H-M-
Tags: query , groupby , sqldataconnection , anonymousobject