/// <summary>
/// Proper constructor.
/// </summary>
/// <param name="version">Store version.</param>
/// <param name="modification">Store modification.</param>
/// <param name="keyBytes">Key bytes for the operation.</param>
/// <param name="storeTransaction">Transaction id that created this operation.</param>
public MetadataOperationData(
int version,
StoreModificationType modification,
ArraySegment <byte> keyBytes,
long storeTransaction)
{
this.version = version;
this.modification = modification;
this.keyBytes = keyBytes;
this.storeTransaction = storeTransaction;
this.Intialize();
}
/// <summary>
/// Called during false progress processing for multi-versioned and historical stores.
/// </summary>
/// <param name="keyLockResourceNameHash"></param>
/// <param name="sequenceNumber">Sequence number at which the false progress occurred.</param>
/// <param name="storeModificationType">Specifies the type of item to be removed.</param>
/// <param name="key"></param>
/// <returns>True and value if the key exists.</returns>
/// <devnote>AddList update not required since it is ok to have more keys then necessary.</devnote>
internal bool UndoFalseProgress(TKey key, ulong keyLockResourceNameHash, long sequenceNumber, StoreModificationType storeModificationType)
{
// In the current model, checkpoint cannot have false progress.
Diagnostics.Assert(this.isReadonly == false, this.traceType, "Write operation cannot come after the differential has become readonly.");
// Find the item sequence number.
var differentialStateVersions = this.ReadVersions(key);
// Remove item.
TVersionedItem <TValue> undoItem = null;
if (differentialStateVersions != null)
{
var previousVersion = differentialStateVersions.PreviousVersion;
if (previousVersion != null && previousVersion.VersionSequenceNumber == sequenceNumber)
{
undoItem = previousVersion;
differentialStateVersions.PreviousVersion = null;
}
else
{
var currentVersion = differentialStateVersions.CurrentVersion;
Diagnostics.Assert(currentVersion != null, this.traceType, "current version cannot be null");
if (currentVersion.VersionSequenceNumber == sequenceNumber)
{
undoItem = currentVersion;
// Update current version and make prev version null.
if (differentialStateVersions.PreviousVersion != null)
{
differentialStateVersions.CurrentVersion = differentialStateVersions.PreviousVersion;
differentialStateVersions.PreviousVersion = null;
}
else
{
// Remove key
this.RemoveKey(key);
}
}
}
if (undoItem != null)
{
switch (storeModificationType)
{
case StoreModificationType.Add:
// Remove implies undoing insert.
Diagnostics.Assert(undoItem is TInsertedItem <TValue>, this.traceType, "unexpected deleted version");
break;
case StoreModificationType.Remove:
// Add implies undoing delete.
Diagnostics.Assert(undoItem is TDeletedItem <TValue>, this.traceType, "unexpected inserted version");
break;
case StoreModificationType.Update:
Diagnostics.Assert(undoItem is TUpdatedItem <TValue> || undoItem is TInsertedItem <TValue>, this.traceType, "unexpected updated version");
break;
}
return(false);
}
}
return(true);
}
