Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6e7fb6cc10ab68ee149964ddd3fd37f99fb66a4ccf591d1e748d0e727965a7e' 
  AND token = 'RzrKcjQREhP15cw3rJE628vUk8XRMiZXYSCn8+N19ps=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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