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zantarel's avatar
zantarel
Helper I
11 months ago
Solved

Error Handling an empty source

Hi all 

I'm querying ARG in PowerQuery, but one of my tables is returning empty, which is breaking the rest of the query. I have added error handling and i'm just trying to basically get an empty table with the correct column names, but I am running into a problem with the empty row that I'm trying to insert... 

 

Current code: 

if Table.HasColumns(Source, "Results") then #table({"id", "name", "type", "tenantId", "kind", "location", "resourceGroup", "subscriptionId", "managedBy", "sku", "plan", "properties", "tags", "identity", "zones", "extendedLocation"}, {null, null, null, null, null, null, null, null, null, null, null, null, null, null, null, null}) else Source

 

This is the code and the error - whatever I put into that first row it returns this error.... 

 

 

 

Would really appreciate the help!! Thanks in advance!

 

Need Help
  • BA_Pete's avatar
    BA_Pete
    11 months ago

    Hi zantarel ,

     

    Not 100% sure what you mean by "one of my tables is returning empty" as there's a couple of ways to interpret this, but I'm assuming it's just completely void i.e. no columns or anything. If so, try something along these lines:

    let
    Source = #table(1, {{1}}),
    remCol = Table.RemoveColumns(Source,{"Column1"}),
    // Error handling from here ===>
    buildAltTable = #table({"id", "name", "type", "tenantId", "kind", "location", "resourceGroup", "subscriptionId", "managedBy", "sku", "plan", "properties", "tags", "identity", "zones", "extendedLocation"}, {}),
    repTable = if List.Count(Table.ColumnNames(remCol)) = 0 then buildAltTable else remCol
in
    repTable

     

    Obviously this can be condensed into a single step, if you prefer, something like this:

    let
    Source = #table(1, {{1}}),
    remCol = Table.RemoveColumns(Source,{"Column1"}),
    // Error handling from here ===>
    repTable = if List.Count(Table.ColumnNames(remCol)) = 0
        then #table({"id", "name", "type", "tenantId", "kind", "location", "resourceGroup", "subscriptionId", "managedBy", "sku", "plan", "properties", "tags", "identity", "zones", "extendedLocation"}, {})
        else remCol
in
    repTable

     

    Pete

3 Replies

  • BA_Pete's avatar
    BA_Pete
    Super User
    11 months ago

    Hi zantarel ,

     

    Not 100% sure what you mean by "one of my tables is returning empty" as there's a couple of ways to interpret this, but I'm assuming it's just completely void i.e. no columns or anything. If so, try something along these lines:

    let
    Source = #table(1, {{1}}),
    remCol = Table.RemoveColumns(Source,{"Column1"}),
    // Error handling from here ===>
    buildAltTable = #table({"id", "name", "type", "tenantId", "kind", "location", "resourceGroup", "subscriptionId", "managedBy", "sku", "plan", "properties", "tags", "identity", "zones", "extendedLocation"}, {}),
    repTable = if List.Count(Table.ColumnNames(remCol)) = 0 then buildAltTable else remCol
in
    repTable

     

    Obviously this can be condensed into a single step, if you prefer, something like this:

    let
    Source = #table(1, {{1}}),
    remCol = Table.RemoveColumns(Source,{"Column1"}),
    // Error handling from here ===>
    repTable = if List.Count(Table.ColumnNames(remCol)) = 0
        then #table({"id", "name", "type", "tenantId", "kind", "location", "resourceGroup", "subscriptionId", "managedBy", "sku", "plan", "properties", "tags", "identity", "zones", "extendedLocation"}, {})
        else remCol
in
    repTable

     

    Pete