Obtain GUID from Oracle

Oracle obtains GUID. Oracle does not want MsSqlServer to have the NEWID () method, but we can use the following method to obtain the Guid SQL statement: SELECT sys_guid () from T_Table, the number of guids queried by the SQL statement = the number of data records in the Table. Where can I obtain the first few pieces of data? top can be used in MsSqlServer, but not in Oracle. SQL statement: SELECT sys_guid () from T_USERS where rownum <2 to obtain the first entry of the Guid. Note 1: When the guid obtained by making asp.net is 'hexadecimal convertible '(I have confirmed 16-> 10 ), so in asp.net, if you want to query through guid, You need to convert each number in Oracle Asp.net to two hexadecimal numbers in Oracle (for example, 241 represents F1)