SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a62ce76b64c8430f8d0286968ad57be28aeaa33896d78ba2fa5f2a6f2cfaf6d7' 
  AND token = '7tkCEXG/ftaOCoeTnmLSKoezU5NbrxTN+PC2lrBnTu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}