SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f8979a1b87be59fe193690639abfe0916dc158c93d54788fd26ce14d2979bac' 
  AND token = 'nO5BiRP5SEQBr35J8b3G9orgpAMEyw8oBeCJRNhdqWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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