PowerExchange for Cassandra User Guide

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Supported Virtual Table Operations

You can use virtual table operations to access, write, or delete rows from a virtual table.

You can perform the following operations in a virtual table:

Read: Use the read operation to retrieve rows from a virtual table.
Insert: Use the insert operation to add one or more rows to a virtual table. Each row that you insert must correspond to a primary key in the source table. If you insert data into a row key that contains data, Cassandra overwrites the original data in the row with the new data.

Cassandra database treats all insert operations as upsert operations.
Update: Use the update operation to update rows in a virtual table. Use the DD_UPDATE constant in an Update Strategy transformation to update rows in a virtual table.

If the collection type is list, sort the corresponding source or target virtual table data in descending order before you pass data to the Update Strategy transformation.
Append: Use the append operation to add an element to the end of the list type.
Delete: Use the delete operation to remove one or more rows from a virtual table. You can use the DD_DELETE constant in an Update Strategy transformation or use a delete command, such as a Pre SQL or Post SQL command, to remove rows.

If the collection type is list, sort the corresponding source or target virtual table data in descending order before you pass data to the Update Strategy transformation.