SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4cf24e2c7e336874e10d00d4dff5564164fcb030a930a033b491e39efa14652f' 
  AND token = '5KqAl4bdxVGNYyCHp34Q7aA2QAIntnM6BqIXNeYOO+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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