SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebb67765dae93703c0aa7b47ee228b84314d25de8d3e738ccbf863a62374569b' 
  AND token = 'WzAGxMANPIifHkvTZJQMBNPfVIDG53zHyNvARW8tVAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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