Rules for Updating Partitioning Columns of a Row-Partitioned Table
The following rules apply to updating the partitioning columns of a row-partitioned
table:
For an UPDATE request that attempts to update the partitioning columns, the partitioning
expression must result in a value between 1 and the number of partitions defined for
that level.
For an UPDATE request that attempts to insert a row, the partitioning expression for
that row must result in a value between 1 and the number of partitions defined for
that level.
You cannot update the system‑derived columns PARTITION and PARTITION#L1 through PARTITION#L62.
Errors, such as divide by zero, can occur during the evaluation of a partitioning
expression. The system response to such an error varies depending on the session mode
in effect at the time the error occurs.
In this session mode …
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Expression evaluation errors roll back this work unit …
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ANSI
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request that contains the aborted request.
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Teradata
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transaction that contains the aborted request.
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Take care in designing your partitioning expressions to avoid expression errors.
For the update to succeed, the session mode and collation at the time the table was
created do not need to match the current session mode and collation. This is because
the partition that contains a row to be updated is determined by evaluating the partitioning
expression on partitioning column values using the table’s session mode and collation.
In updating rows in a table defined with a character partitioning, if the collation
for the table is either MULTINATIONAL or CHARSET_COLL and the definition for the collation
has changed since the table was created, the system aborts any request that attempts
to update a row in the table and returns an error to the requestor.
If the partitioning expression for a table involves Unicode character expressions
or literals and the system has been backed down to a release that has Unicode code
points that do not match the code points that were in effect when the table or join
index was defined, Teradata Database aborts any attempts to update rows in the table
and returns an error to the requestor.