SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9463519ee581f4fa914b6281f22aa122f242e673a688b917b7bf239cb469fba9' 
  AND token = 'vTE41W/PLCMdwIaQYp30eJp1D1zD1H+OK/RIyWVWYTQ=' 
  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"
    }
  }
}