SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddb502efe98513b63985c881879296a185ca33a78eeea33e95acd358e883e8f5' 
  AND token = 'RXBqWlJaUEfg9fhgdwbYluiWDyYU0dJqjqadGP/RPLI=' 
  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"
    }
  }
}