Insitial commit of mquery / DAX to power a Gantt chart in PowerBI

-- estimated_duration

let

    Source = PostgreSQL.Database("hgis-prj-mgmt:5438", "proj_status"),

    f_o_isg_vext_task_duration = Source{[Schema="f_o_isg",Item="vext_task_duration"]}[Data],

    JoinedTables = Table.NestedJoin(f_o_isg_vext_task_duration, {"title"}, NumericalData, {"Title"}, "title_matches", JoinKind.Inner),

       ExpandedTable = Table.ExpandTableColumn(JoinedTables, "title_matches", {"effort_wt"}, {"NumericalData.effort_wt"}),

     weighted_fte = Table.AddColumn(ExpandedTable, "weighted_fte", each [estimated_fte_months] * [NumericalData.effort_wt]),

    wt_dur_day = Table.AddColumn(weighted_fte, "weighted_duration_days", each [def_task_dur_days] *  [NumericalData.effort_wt]),

    wt_dur_mo = Table.AddColumn(wt_dur_day, "weighted_duration_months", each [def_task_dur_mo] *  [NumericalData.effort_wt]),

    #"Changed Type" = Table.TransformColumnTypes(wt_dur_mo,{{"weighted_duration_days", type number}, {"weighted_duration_months", type number}, {"weighted_fte", type number}})

in

    #"Changed Type"

-- estimatedcost

let

    Source = PostgreSQL.Database("hgis-prj-mgmt:5438", "proj_status"),

    f_o_isg_v_task_cost_estimate = Source{[Schema="f_o_isg",Item="vext_task_cost_estimate"]}[Data],

     JoinedTables = Table.NestedJoin(f_o_isg_v_task_cost_estimate, {"title"}, NumericalData, {"Title"}, "title_matches", JoinKind.Inner),

       ExpandedTable = Table.ExpandTableColumn(JoinedTables, "title_matches", {"effort_wt"}, {"NumericalData.effort_wt"}),

    weighted_cost = Table.AddColumn(ExpandedTable, "weighted_cost", each [estimated_cost] * [NumericalData.effort_wt]),

  #"Changed Type" = Table.TransformColumnTypes(weighted_cost,{"weighted_cost", type number})

in

    #"Changed Type"

-- projectscheduie

ProjectSchedule = 

VAR StartDate = TODAY() // A fixed start date for all parallel schedules

// This variable first joins the necessary data from all three tables.

// It iterates over the central 'metadata' table and uses RELATED()

// to pull in columns from the related 'v_ian_duration' and 'FeaturePrioritization' tables.

VAR TasksJoined =

    ADDCOLUMNS(

        'metadata',

        // "Platform", 'metadata'[Platform],

        "Duration", RELATED('estimated duration'[weighted_duration_months]),

        "Rank", RELATED('NumericalData'[mgt_weighted_rank])

    )

VAR TasksSorted =

    ADDCOLUMNS(

        TasksJoined,

        // A hidden column for stable sorting using the Rank

        "__SortValue", [Rank]

    )

// Step 1: Create a table with the TaskStartDate column

VAR TasksWithStartDates =

    ADDCOLUMNS(

        TasksSorted,

        // Calculate the cumulative duration of all preceding tasks

        // using SUMX and EARLIER. This is the core logic for sequencing.

        "TaskStartDate",

            VAR CumulativeDuration =

                SUMX(

                    // The FILTER has been modified to only sum durations for tasks

                    // that share the same 'Primary Resource'

                    FILTER(

                        TasksSorted,

                        // Group the calculation by Primary Resource

                        [Primary Resource] = EARLIER([Primary Resource]) &&

                        // Then, apply the sorting logic for the cumulative sum

                        (

                            [__SortValue] < EARLIER([__SortValue]) || (

                                [__SortValue] = EARLIER([__SortValue]) &&

                                [title] < EARLIER([title])

                            )

                        )

                    ),

                    [Duration]

                )

            RETURN

                // EDATE is used here to correctly add the cumulative months to the start date.

                EDATE(StartDate, CumulativeDuration)

    )

// Step 2: Create a new table that now has access to the TaskStartDate column

VAR TasksWithBothDates =

    ADDCOLUMNS(

        TasksWithStartDates,

        "TaskEndDate",

            // The end date is calculated by adding the task's duration in months to its start date.

            EDATE([TaskStartDate], [Duration])

    )

// Return the final table, selecting only the necessary columns

RETURN

    SELECTCOLUMNS(

        TasksWithBothDates,

        "Title", [title],

        "Primary Resource", [Primary Resource],

        "Rank", [Rank],

        "Duration", [Duration],

        "StartDate", [TaskStartDate],

        "EndDate", [TaskEndDate]

    )