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Interface COM.cloudscape.types.DatabaseInstant


public interface DatabaseInstant
extends java.io.Serializable
Copyright © 1998-2000, Informix Software, Inc. All rights reserved.

This interface is used in the column SYS.SYSSYNCINSTANTS.INSTANT.

A DatabaseInstant is a quantity which the database associates with events to collate them.

Assume a database associates a DatabaseInstant to an event E1. We call this I(E1). Also assume the same Database associates a DatabaseInstant to a second event E2. We call this I(E2). By definition

  1. If I(E1) < I(E2) event E1 occurred before event E2
  2. If I(E2) = I(E2) event E1 is the same event as E2
  3. If I(E1) > I(E2) event E1 occurred after event E2

It is not meaningful to compare a DatabaseInstant from one database with a DatabaseInstant from another. The result of such a comparison is undefined. Because a database may construct, store and compare huge numbers of DatabaseInstants, this interface does not require an implementation to notice when a caller compares a DatabaseInstants from different databases.

Any implementation of this interface must implement value equality, thus implementing equals() and hashCode() methods.


Method Index

 o lessThan(DatabaseInstant)
Return true if this DatabaseInstant is before another DatabaseInstant from the same database.

Method Detail

 o lessThan
public boolean lessThan(DatabaseInstant other)
          Return true if this DatabaseInstant is before another DatabaseInstant from the same database.
Parameters:
other - a DatabaseInstant from the same database as this.
Returns:
the comparison result. If 'other' is from another database the result is undefined.

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