SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c72387214d359091c957692c304dd6d6c4c551d2b03276f676a67fa7564ba66d' 
  AND token = 'lt67Nxc+vhwYhDG8SQlHIiiQsCConxgoDGJLaEcuwho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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