Create a global temporary table

Use the following commands to create and identify global temporary tables:

To create a global temporary table:

create global temp table <table name> (colname datatype)

create global temp table <table name> as select * from <table name>

To identify a global temporary table in the database, use \d, and verify the value for Type:

If GLOBAL is specified, then a global temporary table is defined.
If LOCAL is specified, then a local temporary table is defined.
If TEMP is specified, then a local temporary table is defined.

GTT.ADMIN(ADMIN)=> \d

List of relations

Schema | Name |       Type       | Owner
-------+------+------------------+-------
ADMIN  | GT1  | GLOBAL TEMP TABLE| ADMIN

(1 row)

Restrictions:

Similarly to local temporary tables, ADD and DROP of columns are not allowed on global temporary tables.
User can't load data in a global temporary table using nzload.
Global Temporary Tables (GTT) cannot be altered once created.
GTT with constraints can not be restored and may result nzrestore failure with following error:
```
Operation not allowed on a Global Temp Table Template.
```