A column has been defined without a name.

How to fix

Ensure that you have a name attribute defined for the each column element.

Problem example:

{
  "tables": [
    {
      "schema": "dbo",
      "name": "Users",
      "columns": [
        {
           // Missing "name" property 
          "dataset": "FirstNames"
        }
      ]
    }
  ]
}

Ensure that you have a name attribute defined for each column element.

{
  "tables": [
    {
      "schema": "dbo",
      "name": "Users",
      "columns": [
        {
          "name": "FirstName",           // Added column name
          "dataset": "FirstNames"
        }
      ]
    }
  ]
}