SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e01c6b8284047e20b2c875c41a0123f98764b03930675d6db5709b9ee74bf899' 
  AND token = 'LTxeV3oRcspHuvDRNg2GKTwpY7WZZzBbI2IyW6+iJnY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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