SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd69728b6e09016329fbfc203c26b7aef289f2c8dfdc6d73ea6e68e649953fba' 
  AND token = '9iy1m8lZAfqn8RUhVFrDMIxTTXzKABgSqjG1CNDzWpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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