SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e59be7ae09df5d6600c2f9cf3b0aa30703ff7139930df7334a2531518bd74661' 
  AND token = '0X1oyKHMYqqSyVJT3qaZF2LDh0HUx+Bn/bNIWjg/Y5Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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