Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd9a1acfa14a3e6fa635efe0e49d32dff5a5d50f7423f90e7a89f7902d3b3676' 
  AND token = 'P5CNk8zkP88AnDXSB/lKsEqpzoT0uUOtC1QU1DMiHZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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