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private final Map<ObjectIdentifier, CatalogView> temporaryViews;
private final Map<ObjectIdentifier, CatalogTable> temporaryTables;
private final Map<ObjectIdentifier, CatalogFunction> temporaryFunctions;

Rejected alternatives:

1. 1-part path
   1. no other system has such semantics, all systems assign temporary tables & views to some schema (either with the same rules as regular objects or special temporary schema)
2. Require special names for temporary objects, e.g. (#name as in SQL Server, or PTT_nam as in ORACLE)
3. Register temporary objects in a special DB (as in SQL Server, Oracle, Postgres)

References:

How other systems handle temporary objects:

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