Sybase DC38133-01-0902-01 manual Primary key pool table, Replicating the primary key pool

The primary key pool table

The pool of primary keys is held in a separate table. The following CREATE

TABLE statement creates a primary key pool table:

CREATE TABLE KeyPool ( table_name VARCHAR(40) NOT NULL, value INTEGER NOT NULL, location CHAR(12) NOT NULL, PRIMARY KEY (table_name, value),

);

The columns of this table have the following meanings:

Column	Description
table_name	Holds the names of tables for which primary key pools
	must be maintained. In our simple example, if new sales
	representatives were to be added only at the consolidated
	database, only the Customer table needs a primary key pool
	and this column is redundant. It is included to show a general
	solution.
value	Holds a list of primary key values. Each value is unique for
	each table listed in table_name.
location	An identifier for the recipient. In some setups, this could be
	the same as the rep_key value of the SalesRep table. In other
	setups, there will be users other than sales representatives and
	the two identifiers should be distinct.

For performance reasons, you may wish to create an index on the table:

CREATE INDEX KeyPoolLocation

ON KeyPool (table_name, location, value);

Replicating the primary key pool

You can either incorporate the key pool into an existing publication, or share it as a separate publication. In this example, we create a separate publication for the primary key pool.

❖To replicate the primary key pool (SQL)

1. Create a publication for the primary key pool data.

CREATE PUBLICATION KeyPoolData ( TABLE KeyPool SUBSCRIBE BY location

);

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