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Client APIs and toolsYou can use the HCL OneDB™ implementation of client APIs to develop applications for HCL OneDB™ database servers.
Change Data Capture API Programmer's GuideThese topics describe how to program applications to process changed data from HCL OneDB™ databases using the HCL® OneDB® Change Data Capture API.The HCL OneDB™ Change Data Capture API Programmer's Guide describes how to program applications to process changed data from HCL OneDB™ databases using the HCL® OneDB® Change Data Capture API.
Change Data Capture recordsThe Change Data Capture (CDC) records are returned by smart large object read functions and contain the captured data and information about the transaction currently being captured.
Format of CDC recordsThe Change Data Capture (CDC) records contain a header that is common to all records, followed by a specific header for the type of CDC record.

Format of CDC records

The Change Data Capture (CDC) records contain a header that is common to all records, followed by a specific header for the type of CDC record.

The CDC_REC_INSERT, CDC_REC_DELETE, CDC_REC_UPDBEF, and CDC_REC_UPDAFT records also contain column data.

The header common to all CDC records describes the size and type of the CDC record.

Table 1. The header common to all CDC records
Section	Size	Description
Header size	4 bytes	The number of bytes in the common and CDC record-specific headers.
Payload size	4 bytes	The number of bytes of data in the record after the common and CDC record-specific headers.
Packet scheme	4 bytes	The packetization scheme number of one of the packetization schemes contained in the syscdcpacketschemes table. The only packetization scheme is `66`, CDC_PKTSCHEME_LRECBINARY.
Record number	4 bytes	The record number of one of the CDC records contained in the syscdcrectypes table.