SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20191609dedcd9071522a4c30084741f4e816e981aafbf49dee517ea5916d7ee' 
  AND token = 'QnFnfOOgrgkso/vBmrD9jn/UVrNJE/iDLtXTTwI87bQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00188

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}