Sybase DC38133-01-0902-01 manual Differences in approach, 440

Differences in approach

There are some features of SQL Remote that must be approached in a different manner in SRE and SRA.

♦Partitioning tables that do not contain the subscription expression

In SRA, publications can contain subqueries, and these allow tables that do not contain a partition expression to nevertheless be distributed properly among subscribers. In SRE, an additional column must be added to such tables, containing a list of subscribers, and triggers must be written to maintain the column. This column can have a maximum size of 255.

☞For descriptions, see “Partitioning tables that do not contain the subscription expression” on page 105 , and “Partitioning tables that do not contain the subscription column” on page 149 .

♦Conflict resolution In SRA, conflict resolution is carried out using a special trigger syntax. In SRE, stored procedures must be written to carry out this task.

☞For descriptions, see “Managing conflicts” on page 120 , and “Managing conflicts” on page 165 .

♦ Storing messages before sending In SRE, a separate table named the stable queue is used to hold changes before replication. In SRA, there is no stable queue; instead, the messages are retrieved from current and old transaction log files.

♦Commands Whereas SQL Remote tasks such as creating publications are carried out using SQL statements in SRA, they are carried out using system stored procedures in SRE.

Adaptive Server Enterprise procedures and Adaptive Server Anywhere statements

In SQL Remote for Adaptive Server Anywhere, SQL statements are used to carry out the tasks that these stored procedures carry out in Adaptive Server Enterprise. The following table lists the SQL Remote procedures, and how they correspond to SQL statements in Adaptive Server Anywhere:

Adaptive Server Enterprise proce-	Corresponding Adaptive Server
dure	Anywhere statement
sp_remote_type	CREATE REMOTE MES-
	SAGE TYPE

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