Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8b2ac104c6ac9d48dae1bc5b24e42a9f3609eb596215a9b5cd7195984d31fc1e' 
  AND token = '9QZ5oUvKqBFqpMSHCfIowy8Yfmbh7ZnWj8W1Nyzyll4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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