Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cdbc6b67c98cdc2aab7ced71f35fbaae84229cbc5f1c7204ccebc07bcc97ac3' 
  AND token = 'z2tdt2ot6DfLc/TJI98JYI5BF2Xn+GrImXEVr0VHfNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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