private long?GetLastOffset()
{
using var context = dbContextCreator.Create();
var entityTypeName = context.Model.FindEntityType(typeof(TEntity))?.GetTableName();
Expression <Func <SqlEventLogEntry, bool> > filter = e => e.EntityType == entityTypeName &&
e.TransactionId < PostgresFunctions.SnapshotMinimalTransactionId(PostgresFunctions.CurrentTransactionIdsSnapshot());
if (!context.Set <SqlEventLogEntry>().Any(filter))
{
return(null);
}
return(context.Set <SqlEventLogEntry>().Where(filter).Max(e => e.Offset));
}
private Expression <Func <SqlEventLogEntry, bool> > BuildEventsSearchCriterion(long?fromOffsetExclusive)
{
Expression <Func <SqlEventLogEntry, bool> > searchCriterion;
if (fromOffsetExclusive.HasValue)
{
searchCriterion = e => e.Offset > fromOffsetExclusive.Value &&
e.EntityType == entityTypeName &&
e.TransactionId < PostgresFunctions.SnapshotMinimalTransactionId(PostgresFunctions.CurrentTransactionIdsSnapshot());
}
else
{
searchCriterion = e => e.EntityType == entityTypeName &&
e.TransactionId < PostgresFunctions.SnapshotMinimalTransactionId(PostgresFunctions.CurrentTransactionIdsSnapshot());
}
return(searchCriterion);
}