Oracle Temp Table (temporary table)

Global temporary represents a globally temporary table
Metadata for temporary tables is stored in the data dictionary

Allocate space for a segment of this table only when the first DML command occurs

The visible range of temporal table data should be session level or transaction level

The on commit keyword determines when a session or transaction level is built, on commit DELETE rows represents the transaction level, on Commit perserve rows represents the session level

DDL commands run only after temporary tables are disconnected from the session

For session level, when the TRUNCATE command occurs, the binding between the session and the staging table is broken, and for the transaction level, the rollback or commit

Some limitations of Oracle temp tables:
Temporary tables cannot be partitioned, clustered, or index organized.
You cannot specify any foreign key constraints on temporary tables.
Temporary tables cannot contain columns of nested table.
You cannot specify the following clauses of the lob_storage_clause:
Tablespace, storage_clause, or logging_clause.
Parallel UPDATE, DELETE and MERGE is not supported for temporary tables.
You cannot specify the nested_table_col_properties or parallel_
clause.
The only part of the segment_attributes_clause can specify for a
temporary table is tablespace.
Distributed transactions is not supported for temporary tables.

Oracle Temp Table (temporary table)