public void DeleteIndex()
{
if (GetViewId() < 0)
{
return;
}
bool success = false;
try
{
database.BeginTransaction();
string[] whereArgs = new string[] { Sharpen.Extensions.ToString(GetViewId()) };
database.GetDatabase().Delete("maps", "view_id=?", whereArgs);
ContentValues updateValues = new ContentValues();
updateValues.Put("lastSequence", 0);
database.GetDatabase().Update("views", updateValues, "view_id=?", whereArgs);
success = true;
}
catch (SQLException e)
{
Log.E(Log.TagView, "Error removing index", e);
}
finally
{
database.EndTransaction(success);
}
}
/// <summary>
/// Deletes the <see cref="Couchbase.Lite.View"/>'s persistent index.
/// The index is regenerated on the next <see cref="Couchbase.Lite.Query"/> execution.
/// </summary>
public void DeleteIndex()
{
if (Id < 0)
{
return;
}
var success = false;
try
{
Database.BeginTransaction();
var whereArgs = new string[] { Sharpen.Extensions.ToString(Id) };
Database.StorageEngine.Delete("maps", "view_id=?", whereArgs);
var updateValues = new ContentValues();
updateValues["lastSequence"] = 0;
Database.StorageEngine.Update("views", updateValues, "view_id=?", whereArgs); // TODO: Convert to ADO params.
success = true;
}
catch (SQLException e)
{
Log.E(Database.Tag, "Error removing index", e);
}
finally
{
Database.EndTransaction(success);
}
}
internal void UpdateIndex()
{
Log.V(Database.Tag, "Re-indexing view {0} ...", Name);
System.Diagnostics.Debug.Assert((Map != null));
if (Id <= 0)
{
var msg = string.Format("View.Id <= 0");
throw new CouchbaseLiteException(msg, new Status(StatusCode.NotFound));
}
Database.BeginTransaction();
var result = new Status(StatusCode.InternalServerError);
Cursor cursor = null;
try
{
var lastSequence = LastSequenceIndexed;
var dbMaxSequence = Database.LastSequenceNumber;
if (lastSequence == dbMaxSequence)
{
// nothing to do (eg, kCBLStatusNotModified)
Log.V(Database.Tag, "lastSequence ({0}) == dbMaxSequence ({1}), nothing to do", lastSequence, dbMaxSequence);
result.SetCode(StatusCode.NotModified);
return;
}
// First remove obsolete emitted results from the 'maps' table:
var sequence = lastSequence;
if (lastSequence < 0)
{
var msg = string.Format("lastSequence < 0 ({0})", lastSequence);
throw new CouchbaseLiteException(msg, new Status(StatusCode.InternalServerError));
}
if (lastSequence == 0)
{
// If the lastSequence has been reset to 0, make sure to remove
// any leftover rows:
var whereArgs = new string[] { Id.ToString() };
Database.StorageEngine.Delete("maps", "view_id=?", whereArgs);
}
else
{
// Delete all obsolete map results (ones from since-replaced
// revisions):
var args = new [] {
Id.ToString(),
lastSequence.ToString(),
lastSequence.ToString()
};
Database.StorageEngine.ExecSQL(
"DELETE FROM maps WHERE view_id=? AND sequence IN ("
+ "SELECT parent FROM revs WHERE sequence>? " + "AND parent>0 AND parent<=?)",
args);
}
var deleted = 0;
cursor = Database.StorageEngine.RawQuery("SELECT changes()");
cursor.MoveToNext();
deleted = cursor.GetInt(0);
cursor.Close();
// Find a better way to propagate this back
// Now scan every revision added since the last time the view was indexed:
var selectArgs = new[] { lastSequence.ToString() };
cursor = Database.StorageEngine.RawQuery("SELECT revs.doc_id, sequence, docid, revid, json, no_attachments FROM revs, docs "
+ "WHERE sequence>? AND current!=0 AND deleted=0 "
+ "AND revs.doc_id = docs.doc_id "
+ "ORDER BY revs.doc_id, revid DESC", CommandBehavior.SequentialAccess, selectArgs);
var lastDocID = 0L;
var keepGoing = cursor.MoveToNext();
while (keepGoing)
{
long docID = cursor.GetLong(0);
if (docID != lastDocID)
{
// Only look at the first-iterated revision of any document,
// because this is the
// one with the highest revid, hence the "winning" revision
// of a conflict.
lastDocID = docID;
// Reconstitute the document as a dictionary:
sequence = cursor.GetLong(1);
string docId = cursor.GetString(2);
if (docId.StartsWith("_design/", StringComparison.InvariantCultureIgnoreCase))
{
// design docs don't get indexed!
keepGoing = cursor.MoveToNext();
continue;
}
var revId = cursor.GetString(3);
var json = cursor.GetBlob(4);
var noAttachments = cursor.GetInt(5) > 0;
// Skip rows with the same doc_id -- these are losing conflicts.
while ((keepGoing = cursor.MoveToNext()) && cursor.GetLong(0) == docID)
{
}
if (lastSequence > 0)
{
// Find conflicts with documents from previous indexings.
var selectArgs2 = new[] { Convert.ToString(docID), Convert.ToString(lastSequence) };
var cursor2 = Database.StorageEngine.RawQuery("SELECT revid, sequence FROM revs "
+ "WHERE doc_id=? AND sequence<=? AND current!=0 AND deleted=0 " + "ORDER BY revID DESC "
+ "LIMIT 1", selectArgs2);
if (cursor2.MoveToNext())
{
var oldRevId = cursor2.GetString(0);
// This is the revision that used to be the 'winner'.
// Remove its emitted rows:
var oldSequence = cursor2.GetLong(1);
var args = new[] { Sharpen.Extensions.ToString(Id), Convert.ToString(oldSequence) };
Database.StorageEngine.ExecSQL("DELETE FROM maps WHERE view_id=? AND sequence=?", args);
if (RevisionInternal.CBLCompareRevIDs(oldRevId, revId) > 0)
{
// It still 'wins' the conflict, so it's the one that
// should be mapped [again], not the current revision!
revId = oldRevId;
sequence = oldSequence;
var selectArgs3 = new[] { Convert.ToString(sequence) };
json = Misc.ByteArrayResultForQuery(
Database.StorageEngine,
"SELECT json FROM revs WHERE sequence=?",
selectArgs3
);
}
}
}
// Get the document properties, to pass to the map function:
var contentOptions = DocumentContentOptions.None;
if (noAttachments)
{
contentOptions |= DocumentContentOptions.NoAttachments;
}
var properties = Database.DocumentPropertiesFromJSON(
json, docId, revId, false, sequence, DocumentContentOptions.None
);
if (properties != null)
{
// Call the user-defined map() to emit new key/value
// pairs from this revision:
// This is the emit() block, which gets called from within the
// user-defined map() block
// that's called down below.
var enclosingView = this;
var thisSequence = sequence;
var map = Map;
if (map == null)
{
throw new CouchbaseLiteException("Map function is missing.");
}
EmitDelegate emitBlock = (key, value) =>
{
// TODO: Do we need to do any null checks on key or value?
try
{
var keyJson = Manager.GetObjectMapper().WriteValueAsString(key);
var valueJson = value == null ? null : Manager.GetObjectMapper().WriteValueAsString(value);
var insertValues = new ContentValues();
insertValues.Put("view_id", enclosingView.Id);
insertValues["sequence"] = thisSequence;
insertValues["key"] = keyJson;
insertValues["value"] = valueJson;
enclosingView.Database.StorageEngine.Insert("maps", null, insertValues);
//
// According to the issue #81, it is possible that there will be another
// thread inserting a new revision to the database at the same time that
// the UpdateIndex operation is running. This event should be guarded by
// the database transaction that the code begun but apparently it was not.
// As a result, it is possible that dbMaxSequence will be out of date at
// this point and could cause the last indexed sequence to be out of track
// from the obsolete map entry cleanup operation, which eventually results
// to duplicated documents in the indexed map.
//
// To prevent the issue above, as a workaroubd, we need to make sure that
// we have the current max sequence of the indexed documents updated.
// This diverts from the CBL's Android code which doesn't have the same issue
// as the Android doesn't allow multiple thread to interact with the database
// at the same time.
if (thisSequence > dbMaxSequence)
{
dbMaxSequence = thisSequence;
}
}
catch (Exception e)
{
Log.E(Database.Tag, "Error emitting", e);
}
};
map(properties, emitBlock);
}
}
}
// Finally, record the last revision sequence number that was
// indexed:
var updateValues = new ContentValues();
updateValues["lastSequence"] = dbMaxSequence;
var whereArgs_1 = new string[] { Id.ToString() };
Database.StorageEngine.Update("views", updateValues, "view_id=?", whereArgs_1);
// FIXME actually count number added :)
Log.V(Database.Tag, "...Finished re-indexing view {0} up to sequence {1} (deleted {2} added ?)", Name, Convert.ToString(dbMaxSequence), deleted);
result.SetCode(StatusCode.Ok);
}
catch (Exception e)
{
throw new CouchbaseLiteException(e, new Status(StatusCode.DbError));
}
finally
{
if (cursor != null)
{
cursor.Close();
}
if (!result.IsSuccessful)
{
Log.W(Database.Tag, "Failed to rebuild view {0}:{1}", Name, result.GetCode());
}
if (Database != null)
{
Database.EndTransaction(result.IsSuccessful);
}
}
}
internal void UpdateIndex()
{
Log.V(Database.Tag, "Re-indexing view " + Name + " ...");
System.Diagnostics.Debug.Assert((Map != null));
if (Id < 0)
{
var msg = string.Format("View.Id < 0");
throw new CouchbaseLiteException(msg, new Status(StatusCode.NotFound));
}
Database.BeginTransaction();
var result = new Status(StatusCode.InternalServerError);
Cursor cursor = null;
try
{
var lastSequence = LastSequenceIndexed;
var dbMaxSequence = Database.LastSequenceNumber;
if (lastSequence == dbMaxSequence)
{
// nothing to do (eg, kCBLStatusNotModified)
var msg = String.Format("lastSequence ({0}) == dbMaxSequence ({1}), nothing to do", lastSequence, dbMaxSequence);
Log.D(Database.Tag, msg);
result.SetCode(StatusCode.Ok);
return;
}
// First remove obsolete emitted results from the 'maps' table:
var sequence = lastSequence;
if (lastSequence < 0)
{
var msg = string.Format("lastSequence < 0 ({0})", lastSequence);
throw new CouchbaseLiteException(msg, new Status(StatusCode.InternalServerError));
}
if (lastSequence == 0)
{
// If the lastSequence has been reset to 0, make sure to remove
// any leftover rows:
var whereArgs = new string[] { Sharpen.Extensions.ToString(Id) };
Database.StorageEngine.Delete("maps", "view_id=@", whereArgs);
}
else
{
// Delete all obsolete map results (ones from since-replaced
// revisions):
var args = new [] {
Id.ToString(),
lastSequence.ToString(),
lastSequence.ToString()
};
Database.StorageEngine.ExecSQL(
"DELETE FROM maps WHERE view_id=@ AND sequence IN ("
+ "SELECT parent FROM revs WHERE sequence>@ " + "AND parent>0 AND parent<=@)",
args);
}
var deleted = 0;
cursor = Database.StorageEngine.RawQuery("SELECT changes()", null); // TODO: Convert to ADO params.
cursor.MoveToNext();
deleted = cursor.GetInt(0);
cursor.Close();
// find a better way to propagate this back
// Now scan every revision added since the last time the view was
// indexed:
var selectArgs = new[] { Convert.ToString(lastSequence) };
cursor = Database.StorageEngine.RawQuery("SELECT revs.doc_id, sequence, docid, revid, json FROM revs, docs "
+ "WHERE sequence>@ AND current!=0 AND deleted=0 " + "AND revs.doc_id = docs.doc_id "
+ "ORDER BY revs.doc_id, revid DESC", CommandBehavior.SequentialAccess, selectArgs);
cursor.MoveToNext();
var lastDocID = 0L;
while (!cursor.IsAfterLast())
{
long docID = cursor.GetLong(0);
if (docID != lastDocID)
{
// Only look at the first-iterated revision of any document,
// because this is the
// one with the highest revid, hence the "winning" revision
// of a conflict.
lastDocID = docID;
// Reconstitute the document as a dictionary:
sequence = cursor.GetLong(1);
string docId = cursor.GetString(2);
if (docId.StartsWith("_design/", StringComparison.InvariantCultureIgnoreCase))
{
// design docs don't get indexed!
cursor.MoveToNext();
continue;
}
var revId = cursor.GetString(3);
var json = cursor.GetBlob(4);
var properties = Database.DocumentPropertiesFromJSON(
json, docId, revId, false, sequence, EnumSet.NoneOf <TDContentOptions>()
);
if (properties != null)
{
// Call the user-defined map() to emit new key/value
// pairs from this revision:
Log.V(Database.Tag, " call map for sequence=" + System.Convert.ToString(sequence
));
// This is the emit() block, which gets called from within the
// user-defined map() block
// that's called down below.
var enclosingView = this;
var thisSequence = sequence;
var map = Map;
if (map == null)
{
throw new CouchbaseLiteException("Map function is missing.");
}
EmitDelegate emitBlock = (key, value) =>
{
// TODO: Do we need to do any null checks on key or value?
try
{
var keyJson = Manager.GetObjectMapper().WriteValueAsString(key);
var valueJson = value == null ? null : Manager.GetObjectMapper().WriteValueAsString(value);
Log.V(Database.Tag, String.Format(" emit({0}, {1})", keyJson, valueJson));
var insertValues = new ContentValues();
insertValues.Put("view_id", enclosingView.Id);
insertValues["sequence"] = thisSequence;
insertValues["key"] = keyJson;
insertValues["value"] = valueJson;
enclosingView.Database.StorageEngine.Insert("maps", null, insertValues);
}
catch (Exception e)
{
Log.E(Database.Tag, "Error emitting", e);
}
};
map(properties, emitBlock);
}
}
cursor.MoveToNext();
}
// Finally, record the last revision sequence number that was
// indexed:
ContentValues updateValues = new ContentValues();
updateValues["lastSequence"] = dbMaxSequence;
var whereArgs_1 = new string[] { Sharpen.Extensions.ToString(Id) };
Database.StorageEngine.Update("views", updateValues, "view_id=@", whereArgs_1);
// FIXME actually count number added :)
Log.V(Database.Tag, "...Finished re-indexing view " + Name + " up to sequence " +
System.Convert.ToString(dbMaxSequence) + " (deleted " + deleted + " added " + "?" + ")");
result.SetCode(StatusCode.Ok);
}
catch (SQLException e)
{
throw new CouchbaseLiteException(e, new Status(StatusCode.DbError));
}
finally
{
if (cursor != null)
{
cursor.Close();
}
if (!result.IsSuccessful())
{
Log.W(Database.Tag, "Failed to rebuild view " + Name + ": " + result.GetCode());
}
if (Database != null)
{
Database.EndTransaction(result.IsSuccessful());
}
}
}
