The schema of an UltraLite database is stored in a proprietary format. Earlier versions of UltraLite databases were stored in several system tables. These system tables can still be queried for backward compatibility (they are in essence system views), but they only contain information about user schema (like tables, columns, indexes) not system schema. For example, you cannot query systable to find the properties of systable itself. You can only query systable to find the properties of user-created tables.
Each UltraLite programming API supports objects and methods that can be used to query the database about its schema. It is recommended that you use these objects and APIs to explore schema rather than querying the system views.
All queries performed on these system views are equivalent to full table scans. Index scans are not supported on these system views.
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