SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62cac70bead65d8a9d1dce76172cddb6fed1977fd2ab6fbd772559d0c0f76134' 
  AND token = 'hZInEXvNpRScpnUxYDAQ8Q8Y5EhJwSdbUnOQtyCL1iE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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