Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d79b3ebc02a0760a3ecb8443ac18878bce2b7e751bbffaade1085dd636de4c6' 
  AND token = 'TsmBTSb4X+tMgPQ35euPk4cKzP6pVyK4gy1Oj6/rqwI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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