Check append condition against events after a position - #921
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The append condition required the highest matching event to be exactly `highestSequenceNumber`. The DCB spec instead fails the append only if a matching event exists after the given position, which may be higher than the last matching event. A caller passing e.g. the global head got a false AppendConditionNotMet. AppendCondition now takes `after` (default 0) and both stores check that no matching event with a higher index exists. The query is required now, since an empty query matches all events.
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DavidBadura
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DanielBadura
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Oct 3, 2026
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The append condition checked that the highest matching event is exactly
highestSequenceNumber. The DCB spec defines it differently: the append fails if an event matching the query exists after the given position, and that position may be higher than the last matching event. So passing anything other than the exact last matching index, like the global head, led to a falseAppendConditionNotMet.AppendConditionnow takesafterinstead ofhighestSequenceNumber, defaulting to 0 (no matching event may exist at all). Both stores check that no matching event with a higher index exists, on the dbal side as aNOT EXISTS (... WHERE events.id > :after). The query is now required, sincenew AppendCondition()would otherwise mean "the store must be empty". For decision models built withStoreDecisionModelBuildernothing changes.