24.5 Data-Dictionary Views For Persistent Data-Guide Information

You can query static data-dictionary views to see which tables have JSON columns with data guide-enabled JSON search indexes and to extract JSON object field information that is recorded in dataguide-enabled JSON search indexes.

Tables that do not have JSON columns with data guide-enabled indexes are not present in the views.

You can use the following views to find columns that have data guide-enabled JSON search indexes. The views have columns TABLE_NAME (the table name), COLUMN_NAME (the JSON column name), and DATAGUIDE (a data guide).

  • USER_JSON_DATAGUIDES — tables owned by the current user

  • ALL_JSON_DATAGUIDES — tables accessible by the current user

  • DBA_JSON_DATAGUIDES — all tables

If the JSON column has a data guide-enabled JSON search index then the value of column DATAGUIDE is the data guide for the JSON column, in flat format as a CLOB instance. If it does not have a data guide-enabled index then there is no row for that column in the view.

You can use the following views to extract JSON field path and type information that is recorded in dataguide-enabled JSON search indexes. The views have columns TABLE_NAME, COLUMN_NAME, PATH, TYPE, and LENGTH. Columns PATH, TYPE, and LENGTH correspond to the values of data-guide fields o:path, type, and o:length, respectively.

  • USER_JSON_DATAGUIDE_FIELDS — tables owned by the current user

  • ALL_JSON_DATAGUIDE_FIELDS — tables accessible by the current user

  • DBA_JSON_DATAGUIDE_FIELDS — all tables

In the case of both types of view, a view whose name has the prefix ALL_ or DBA_ also has column OWNER, whose value is the table owner.

See Also:

Parent topic: JSON Data Guide