Migrating Replication Server data to Adaptive Server 12.5

Adaptive Server version 12.5 can generate data wider than what Replication Server version 12.1 can handle, regardless of Adaptive Server’s page size. For example, a 2K page Adaptive Server can have more than 250 columns, and columns wider than 255 bytes.

Replication Server version 12.1 and earlier cannot handle wide data. If wide data is passed to it by the RepAgent, different Replication Server threads may shut down.

When the RepAgent connects to the Replication Server, it returns an LTL version. This version and data limits filter mode setting determine how RepAgent treats wide data. The Replication Server version and LTL version compatibility is as follows:

**Table 6-1: Replication Server and LTL versions**
Replication Server version	LTL version
12.1 and earlier	< 400
post-12.1	>= 400

The compatibility for the limits, depending on the LTL version is as follows:

**Table 6-2: Replication Server column counts/width limits**
Property	12.1 and earlier Replication Server	Post-12.1 Replication Server
column count	250	65535
column width	255	65535

For Adaptive Server 12.5 connecting to Replication Server version 12.1 and earlier, the default data limits filter mode is “stop.” The RepAgent shuts down when it encounters data that is wider than what Replication Server can handle. If data limits filter mode is set to “skip,” the RepAgent skips over wide data that is wider than what Replication Server can handle, and logs an informational message when it does so.

If data limits filter mode is set to “truncate,” the RepAgent truncates wide data so that the Replication Server can handle it. In Replication Servers version 12.1 and earlier, if the table or stored procedure has more than 250 columns or parameters, only the first 250 columns or parameters are sent. If the column or parameter is wider than 255, only the first 255 bytes are sent.

If data limits filter mode is set to “off”, wide data is sent to Replication Server, and may cause errors in Replication Server.

Replication Server identifies all connections by servername.database; this means that after migration, you must change the name of the target server to the name of the source server.