ORA-01792 maximum number of columns in a table or view is 1000
Cause: An attempt was made to create a table or view with more than 1000 columns, or to add more columns to a table or view which pushes it over the maximum allowable limit of 1000. Note that unused columns in the table are counted toward the 1000 column limit.
Action: If the error is a result of a CREATE command, then reduce the number of columns in the command and resubmit. If the error is a result of an ALTER TABLE command, then there are two options:
* If the table contained unused columns, remove them by executing ALTER TABLE DROP UNUSED COLUMNS before adding new columns.
* Reduce the number of columns in the command and resubmit.

ORA-01793 maximum number of index columns is 32
Cause: While creating an index, more than 32 columns were specified.
Action: Remove some columns from the index definition. If all the columns indexed are required, split them into two indexes.

ORA-01794 maximum number of cluster columns is 32
Cause: More than 32 columns were specified in the cluster key.
Action: Remove some of the columns from the cluster key definition. Consider concatenating multiple character strings into a single column.

ORA-01795 maximum number of expressions in a list is 1000
Cause: More than 254 columns or expressions were specified in a list.
Action: Remove some of the expressions from the list.

NOTE(10.2 Concepts):
No more than 32 columns can form a regular composite index. For a bitmap
index, the maximum number columns is 30. A key value cannot exceed roughly
half (minus some overhead) the available data space in a data block.

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