How to replace a value based on multiple conditions

HI davidoz,

You can try to add a custom column with the below if statement expressions to do replace value operations:

    #"Added Custom" =
        Table.AddColumn(#"Changed Type","Replace",
            each
                if
                    [PHASE_NAME] = "Flowback" and [TYPE] = "Separators > 100-285psi Storage Separator"
                then
                    if [JOB] = "DJ-229" then "ST-0033"
                    else 
                        if [JOB] = "DJ-50" then "ST-0014"
                    else 
                        if [JOB] = "DJ-85" then "ST-0098"
                    else
                        [NAME]
                else
                    [NAME]
        )

Full query:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WcsvJL09KTM5W0lEKTi1ILEosyS8qVogpNTAwTlUwNDDQNbIwLSjOVAgGiiempyrAFQE1uHjpGhlZAhk+wbpA9cZKsToUG2hqADPPxIQa5lmYwswzNKSGeUaGVPawhakhsgtjAQ==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [PHASE_NAME = _t, TYPE = _t, JOB = _t, NAME = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"PHASE_NAME", type text}, {"TYPE", type text}, {"JOB", type text}, {"NAME", type text}}),
    #"Added Custom" =
        Table.AddColumn(#"Changed Type","Replace",
            each
                if
                    [PHASE_NAME] = "Flowback" and [TYPE] = "Separators > 100-285psi Storage Separator"
                then
                    if [JOB] = "DJ-229" then "ST-0033"
                    else 
                        if [JOB] = "DJ-50" then "ST-0014"
                    else 
                        if [JOB] = "DJ-85" then "ST-0098"
                    else
                        [NAME]
                else
                    [NAME]
        )
in
    #"Added Custom"

Regards,

Xiaoxin Sheng