SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1eefff005bccaa68db5daa61e57d953b9d41a2141e8e3fcd3f753a2e856b03d' 
  AND token = '2A17ad6k9StM7gyidgJflPI+5yq/NVKeSfj4/dBENWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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