# Striim 3.9.6 documentation

The output data type for MSSQLReader is WAEvent. The elements are:

• OperationName: INSERT, UPDATE, or DELETE

• PK_UPDATE: for UPDATE only, true if the primary key value was changed, otherwise false

• TxnID: transaction ID

• TimeStamp: timestamp from the CDC log

• TableName: fully qualified name of the table . It is present but null for key-sequenced files and key-sequenced tables that have a user-defined primary key.

By default, values for TxnID and TimeStamp are included only for the first record of a new transaction (for more details, see FetchTransactionMetadata in MSSQLReader properties).

To retrieve the values for these fields, use the META() function. See Parsing the fields of WAEvent for CDC readers.

data: an array of fields, numbered from 0, containing:

• for an INSERT or DELETE operation, the values that were inserted or deleted

• for an UPDATE, the values after the operation was completed

To retrieve the values for these fields, use SELECT ... (DATA[]). See Parsing the fields of WAEvent for CDC readers.

before (for UPDATE operations only): the same format as data, but containing the values as they were prior to the UPDATE operation

dataPresenceBitMap, beforePresenceBitMap, and typeUUID are reserved and should be ignored.