Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '715f6ca17ea28231dd50c8355cde85a470d0e2599bf03e6f5d0d3b5716cc593a' 
  AND token = 'Y6wZqMPwURpc/OzPwn1Ez+6Np5RHyDGbbRxs3lA52q4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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