SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cdd6097b7248847859d52e4e8e23157e3212462ba15a9e7622031cfbdca015ec' 
  AND token = 'KvChgjzvjCpNU1CydxHMn4ANi82BpEpIy6h4eFJIpCM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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