SQL> create table source ( lat number, lng number);
Table created.
SQL> insert into source values (145.516531118182,-37.8744300272727);
1 row created.
SQL> insert into source values (123.345,-23.35634);
1 row created.
SQL> insert into source values (90.134,-76.234524);
1 row created.
SQL>
SQL>
SQL> create table t ( s sdo_geometry);
Table created.
SQL> insert into t
2 select SDO_GEOMETRY(2001,4283,MDSYS.SDO_POINT_TYPE(lat,lng,NULL),NULL,NULL)
3 from source;
3 rows created.