Bigquery add columns to table schema

Question

I am trying to add new column to BigQuery existing table. I have tried bq command tool and API approach. I get following error when making call to Tables.update().

Answer 1

In my case I was trying to add a REQUIRED field to a template table, and was running into this error. Changing the field to NULLABLE , let me update the table.

Also more recent version on updates for anybody stumbling from Google.

#To create table
bq mk --schema domain:string,pageType:string,source:string -t Project:Dataset.table
#Or using schema file
bq mk --schema SchemaFile.json -t Project:Dataset.table


#SchemaFile.json format
[{                                                                                                                                                                                                                                                
  "mode": "REQUIRED",
  "name": "utcTime",
  "type": "TIMESTAMP"
},    
{
  "mode": "REQUIRED",
  "name": "domain",
  "type": "STRING"
},  
{
  "mode": "NULLABLE",
  "name": "testBucket",
  "type": "STRING"
},  
{
  "mode": "REQUIRED",
  "name": "isMobile",
  "type": "BOOLEAN"                                                                                                                                                                                                                       
},
{
  "mode": "REQUIRED",
  "name": "Category",
  "type": "RECORD",
  "fields": [
    {
      "mode": "NULLABLE",
      "name": "Type",
      "type": "STRING"
     },
     {
       "mode": "REQUIRED",
       "name": "Published",
       "type": "BOOLEAN"
     }
    ]
}]

# TO update
bq update --schema UpdatedSchema.json -t Project:Dataset.table
# Updated Schema contains old and any newly added columns 

Some docs for template tables