Appendix A: Distribution Database Schema

Shadow tables for primary tables with large objects

When you create a primary article for a table with one or more large-object columns, ASE Replicator creates a shadow table with the columns described in Table A-19.

**Table A-19: Shadow table with large object**
Column name	Datatype	Description
conn_id	numeric(18,0)	ID of the primary connection
txid_page	int	The transaction ID page in the transaction log table
txid_row	smallint	The transaction ID row in the transaction log table
log_ts_high	smallint	Log timestamp high value in the transaction log table
log_ts_low	int	Log timestamp low value in the transaction log table
opid_page	int	The operation ID page in the transaction log table
opid_row	smallint	The operation ID row in the transaction log table
op_code	tinyint	Type of operation
op_xstat	int	Identifies operation as either update or delete
image_type_	char(1)	Identifies operation type or procedure execution
pkey	numeric(5,0)	Primary key column(s) value
col1	Specified in primary object	Column for a published field in the primary object
col2	rpl_clob	Column for a published large-object (text) field in the primary object
... coln	...	... Additional column for each published field in the primary object

Except for large-object primary table columns, the shadow table column for each published field has the datatype of the published field, and each row contains the data from that primary column for the transaction operation identified by that row.

For each large-object primary table column, the shadow table column has a user-defined Boolean datatype that identifies the type of large-object data in the primary column, and the value of that Boolean indicates whether a change was made in the primary column data by the transaction operation identified by that row.

The user-defined Boolean datatypes are:

rpl_blob – indicates image primary column data.
rpl_clob – indicates text primary column data.
rpl_uclob – indicates unitext primary column data.
rpl_java – indicates java primary column data.

All of these datatypes map to the Adaptive Server bit datatype.

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