SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c35217088744d273cca2858c105707a62254f14651aeaaf866b8d08cb7986779' 
  AND token = 'm0GcViE8vJ+jwPGTzLJt6AnqrGAg1gp0L5r3GPu4KKo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}