Overview of Heterogeneous Datatype Support

If you are replicating information between Adaptive Servers, datatype translations are normally unnecessary. However, you can use HDS to perform datatype translations when datatypes differ in the primary and replicate databases.

You can use HDS capabilities when replicating between:

Adaptive Server databases – one Adaptive Server datatype to another Adaptive Server datatype
Like non-Sybase databases – for example, DB2 TIMESTAMP to DB2 DATE
Heterogeneous non-Sybase databases – Oracle to DB2, for example
Adaptive Server and non-Sybase databases – Adaptive Server to Oracle, for example

HDS handles incompatibilities between the datatypes of the primary data server and the replicate data server. In general, these incompatibilities are of four types:

Incompatible ranges – for example, the range of acceptable dates for Sybase datetime is January 1, 1753 through December 31, 9999. Another data server, however, may only allow dates from January 1, 0001 through December 31, 9999.
Incompatible formatting – for example, the primary data server date format is “CCYY-MM-DD,” but the replicate data server requires a date format of “MM/DD/CCYY.”
Incompatible length – for example, the primary table may have a column with a character length of 10, but the column in the replicate table has a length of 15.
Incompatible delimiters – for example, Sybase delimits binary data with an “0x” prefix, whereas another data server may surround binary data with single quotation marks.

The Replication Agent for each data server delivers replicate values to Replication Server in a datatype format that Replication Server understands, which includes the literal value, delimiter information, and other datatype attributes. Replication Server handles the value as its base datatype—one of the native Replication Server datatypes described in the Replication Server Reference Manual.

You can implement datatype translations in two ways:

Class-level translations – translate all instances of a datatype for a particular connection.

Create a connection specifying a connection profile for your non-ASE database. The connection profile includes the class-level translation. See Replication Server Reference Manual > Replication Server Commands > create connection using profile.
Column-level translations – translate all instances of a column described by a table replication definition.

Use the map to clause for column-level translations.