An ActiveRecord::StatementInvalid occurred in service_visits#index

An ActiveRecord::StatementInvalid occurred in service_visits#index:

 PG::SyntaxError: ERROR:  syntax error at or near ")"
LINE 3: ..._type_id = service_visit_types.id WHERE (locations.id IN ())
                                                                    ^

 app/datatables/service_visits_datatable.rb:15:in `as_json'


-------------------------------
Request:
-------------------------------

 * URL        : https://full-db.test.bikelink.org/service_visits.json?sEcho=1&iColumns=8&sColumns=%2C%2C%2C%2C%2C%2C%2C&iDisplayStart=0&iDisplayLength=50&mDataProp_0=0&sSearch_0=&bRegex_0=false&bSearchable_0=true&bSortable_0=true&mDataProp_1=1&sSearch_1=&bRegex_1=false&bSearchable_1=true&bSortable_1=true&mDataProp_2=2&sSearch_2=&bRegex_2=false&bSearchable_2=true&bSortable_2=true&mDataProp_3=3&sSearch_3=&bRegex_3=false&bSearchable_3=true&bSortable_3=true&mDataProp_4=4&sSearch_4=&bRegex_4=false&bSearchable_4=true&bSortable_4=true&mDataProp_5=5&sSearch_5=&bRegex_5=false&bSearchable_5=true&bSortable_5=true&mDataProp_6=6&sSearch_6=&bRegex_6=false&bSearchable_6=true&bSortable_6=true&mDataProp_7=7&sSearch_7=&bRegex_7=false&bSearchable_7=true&bSortable_7=false&sSearch=&bRegex=false&iSortCol_0=0&sSortDir_0=desc&iSortingCols=1&_=1625159163829
 * HTTP Method: GET
 * IP address : 98.35.154.160
 * Parameters : {"sEcho"=>"1", "iColumns"=>"8", "sColumns"=>",,,,,,,", "iDisplayStart"=>"0", "iDisplayLength"=>"50", "mDataProp_0"=>"0", "sSearch_0"=>"", "bRegex_0"=>"false", "bSearchable_0"=>"true", "bSortable_0"=>"true", "mDataProp_1"=>"1", "sSearch_1"=>"", "bRegex_1"=>"false", "bSearchable_1"=>"true", "bSortable_1"=>"true", "mDataProp_2"=>"2", "sSearch_2"=>"", "bRegex_2"=>"false", "bSearchable_2"=>"true", "bSortable_2"=>"true", "mDataProp_3"=>"3", "sSearch_3"=>"", "bRegex_3"=>"false", "bSearchable_3"=>"true", "bSortable_3"=>"true", "mDataProp_4"=>"4", "sSearch_4"=>"", "bRegex_4"=>"false", "bSearchable_4"=>"true", "bSortable_4"=>"true", "mDataProp_5"=>"5", "sSearch_5"=>"", "bRegex_5"=>"false", "bSearchable_5"=>"true", "bSortable_5"=>"true", "mDataProp_6"=>"6", "sSearch_6"=>"", "bRegex_6"=>"false", "bSearchable_6"=>"true", "bSortable_6"=>"true", "mDataProp_7"=>"7", "sSearch_7"=>"", "bRegex_7"=>"false", "bSearchable_7"=>"true", "bSortable_7"=>"false", "sSearch"=>"", "bRegex"=>"false", "iSortCol_0"=>"0", "sSortDir_0"=>"desc", "iSortingCols"=>"1", "_"=>"1625159163829", "controller"=>"service_visits", "action"=>"index", "format"=>"json"}
 * Timestamp  : 2021-07-01 17:06:05 UTC
 * Server : sites-2.test.bikelink.org
   * Rails root : /var/www/full-db
 * Process: 23092

-------------------------------
Session:
-------------------------------

 * session id: [FILTERED]
 * data: {"session_id"=>"fb47cfb7cac182ed9a11b64c50a48675",
  "warden.user.person.key"=>[[9408], "vsyv6VyJTKPbFi4gbDnm"],
  "_csrf_token"=>"lmWxkvYXCJ656F0MLvAE2bcYYQzOhie6Y6BFpzeVJNo="}

-------------------------------
Backtrace:
-------------------------------

 app/datatables/service_visits_datatable.rb:15:in `as_json'
 app/controllers/service_visits_controller.rb:64:in `block (2 levels) in index'
 app/controllers/service_visits_controller.rb:48:in `index'
Reload