SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '986248d643020c026a642574fe484180bfc4915f49d3746ceeabd93ac0b5e583' 
  AND token = 'vJl3BvdrtqHDIZg+vwg3VsZ4rJnxynyZImasYSCs6lc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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