SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38d21c0022c76a8f6d3c5e1948b936a94499245da0ac09b7672e32c12d1fc10e' 
  AND token = '0BgsXNTUNBUjsVq1U/XdOui758TarE8YdzNvmFBlrHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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