A constraint is defined containing an unknown column.

How to fix

Ensure that the column defined in the constraint exists in the table.

Problem example:

{
  "tables": [
    {
      "schema": "dbo",
      "name": "Users",
      "constraints": [
        {
          "type": "Unique",
          "columns": ["Address"]         // Column does not exist in the Users table
        }
      ]
    }
  ]
}

Ensure that you have at least one column defined per constraint:

{
   "tables" : [
     {
       "schema" :  "dbo" ,
       "name" :  "Users" ,
       "constraints" : [
         {
           "type" :  "Unique" ,
           "columns" : [ "UserId" ]           // Column does exist in the Users table
         }
       ]
     }
   ]
}