SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e123659e5d90e572ef63d9f393f2e0c807da931e596e6b0e3047a6390992d78' 
  AND token = 'ChtaGRn8SF6Btn24CeJeRuk21/NSeEZcq2CrdMv4SV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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