Sequences and Identity Columns
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Sequences are supported on source and target tables for unidirectional, bidirectional, and multi- directional implementations.
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Identity columns created using the
GENERATED BY DEFAULT AS IDENTITY
clause are supported on source and target tables, for unidirectional, bidirectional, and multi- directional implementations. -
Identity columns created using the
GENERATED ALWAYS AS IDENTITY
clause are not supported in target database tables and the Identity property should be removed from target tables or changed toGENERATED BY DEFAULT AS IDENTITY
. -
For bidirectional and multi-directional implementations, define the Identity columns and sequences with an
INCREMENT BY
value equal to the number of servers in the configuration, with a differentMINVALUE
for each one.For example,
MINVALUE
/INCREMENT BY
values for a bidirectional, two-database configuration would be as follows:Database1, set the
MINVALUE
at 1 with anINCREMENT BY
of 2.Database2, set the
MINVALUE
at 2 with anINCREMENT BY
of 2.For example,
MINVALUE
/INCREMENT BY
values for a multi-directional, three-database configuration would be as follows:Database1, set the
MINVALUE
at 1 with anINCREMENT BY
of 3.Database2, set the
MINVALUE
at 2 with anINCREMENT BY
of 3.Database3, set the
MINVALUE
at 3 with anINCREMENT B
Y of 3.