public void Remove <T>(T value, long index, IIndexedObjectComparer <T> c)
{
CheckReadOnly();
// Search for the position of the last value in the set,
long p1, p2;
SearchFirstAndLast(value, c, out p1, out p2);
// If the value isn't found report the error,
if (p1 < 0)
{
throw new ApplicationException("Value '" + value + "' was not found in the set.");
}
IIndexCursor cursor = GetCursor(p1, p2);
while (cursor.MoveNext())
{
if (cursor.Current == index)
{
// Remove the value and return
cursor.Remove();
return;
}
}
}
public void Insert <T>(T value, long index, IIndexedObjectComparer <T> c)
{
CheckReadOnly();
// Search for the position of the last value in the set,
long pos = SearchLast(value, c);
// If pos < 0 then the value was not found,
if (pos < 0)
{
// Correct it to the point where the value must be inserted
pos = -(pos + 1);
}
else
{
// If the value was found in the set, insert after the last value,
++pos;
}
// Insert the value by moving to the position, shifting the data 8 bytes
// and writing the long value.
file.Position = (pos * 8);
file.Shift(8);
fileWriter.Write(index);
}
public bool InsertUnique <T>(T value, long index, IIndexedObjectComparer <T> c)
{
CheckReadOnly();
// Search for the position of the last value in the set,
long pos = SearchLast(value, c);
// If pos < 0 then the value was not found,
if (pos < 0)
{
// Correct it to the point where the value must be inserted
pos = -(pos + 1);
}
else
{
// If the value was found in the set, return false and don't change the
// list.
return(false);
}
// Insert the value by moving to the position, shifting the data 8 bytes
// and writing the long value.
file.Position = (pos * 8);
file.Shift(8);
fileWriter.Write(index);
// Return true because we changed the list,
return(true);
}
public DbIndex GetIndex(string columnName)
{
CheckColumnNameValid(columnName);
StringDictionary p = TableProperties;
long columnId = p.GetValue(columnName + ".id", -1);
if (columnId == -1)
{
throw new ApplicationException("Column '" + columnName + "' not found");
}
if (!p.GetValue(columnName + ".index", false))
{
throw new ApplicationException("Column '" + columnName + "' is not indexed");
}
// Fetch the index object,
IDataFile df = GetDataFile(GetIndexIdKey(columnId));
SortedIndex list = new SortedIndex(df);
// And return it,
IIndexedObjectComparer <string> comparer = GetIndexComparerFor(columnName, columnId);
return(new DbIndex(this, currentVersion, comparer, columnId, list));
}
public long SearchLast <T>(T value, IIndexedObjectComparer <T> c)
{
long low = 0;
long high = Count - 1;
return(SearchLast(value, c, low, high));
}
internal DbIndex(DbIndex source)
{
table = source.table;
tableVersion = source.tableVersion;
collator = source.collator;
columnid = source.columnid;
index = source.index;
start = source.start;
end = source.end;
}
internal Directory(ITransaction transaction, Key directoryPropertiesKey, Key propertySetKey, Key indexSetKey, short itemKeyType, int itemKeyPrimary)
{
this.transaction = transaction;
this.directoryPropertiesKey = directoryPropertiesKey;
this.indexSetKey = indexSetKey;
this.propertySetKey = propertySetKey;
this.itemKeyType = itemKeyType;
this.itemKeyPrimary = itemKeyPrimary;
collator = new ItemComparer(this);
}
private long SearchFirst <T>(T value, IIndexedObjectComparer <T> c, long low, long high)
{
if (low > high)
{
return(-1);
}
while (true)
{
// If low is the same as high, we are either at the first value or at
// the position to insert the value,
if ((high - low) <= 4)
{
for (long i = low; i <= high; ++i)
{
file.Position = (i * 8);
long val = fileReader.ReadInt64();
int res = c.Compare(val, value);
if (res == 0)
{
return(i);
}
if (res > 0)
{
return(-(i + 1));
}
}
return(-(high + 2));
}
// The index half way between the low and high point
long mid = (low + high) >> 1;
// Reaf the middle value from the data file,
file.Position = (mid * 8);
long midVal = fileReader.ReadInt64();
// Compare it with the value
int res1 = c.Compare(midVal, value);
if (res1 < 0)
{
low = mid + 1;
}
else if (res1 > 0)
{
high = mid - 1;
}
else // if (res == 0)
{
high = mid;
}
}
}
private void AddRowToIndexSet(long rowid)
{
// Get the set of columns that are indexed in this table,
string[] indexedCols = IndexedColumns;
foreach (String col in indexedCols)
{
// Resolve the column name to an id, turn it into a OrderedList64Bit,
// and insert the row in the correct location in the index,
long columnid = GetColumnId(col);
IDataFile df = GetDataFile(GetIndexIdKey(columnid));
SortedIndex index = new SortedIndex(df);
IIndexedObjectComparer <string> indexComparer = GetIndexComparerFor(col, columnid);
index.Insert(GetValue(rowid, columnid), rowid, indexComparer);
}
}
private void SearchFirstAndLast <T>(T value, IIndexedObjectComparer <T> c, out long first, out long last)
{
long low = 0;
long high = Count - 1;
if (low > high)
{
first = -1;
last = -1;
return;
}
while (true)
{
// If low is the same as high, we are either at the first value or at
// the position to insert the value,
if ((high - low) <= 4)
{
first = SearchFirst(value, c, low, high);
last = SearchLast(value, c, low, high);
return;
}
// The index half way between the low and high point
long mid = (low + high) >> 1;
// Reaf the middle value from the data file,
file.Position = (mid * 8);
long midVal = fileReader.ReadInt64();
// Compare it with the value
int res = c.Compare(midVal, value);
if (res < 0)
{
low = mid + 1;
}
else if (res > 0)
{
high = mid - 1;
}
else // if (res == 0)
{
first = SearchFirst(value, c, low, high);
last = SearchLast(value, c, low, high);
return;
}
}
}
public void AddIndex(string columnName, string culture)
{
CheckColumnNameValid(columnName);
StringDictionary p = TableProperties;
// Check the column name exists,
long columnid = p.GetValue(columnName + ".id", -1);
if (columnid == -1)
{
throw new ApplicationException("Column " + columnName + " not found");
}
// Check if index property set,
if (p.GetValue(columnName + ".index", false))
{
throw new ApplicationException("Index already on column " + columnName);
}
// Check the collator encoded string,
if (culture != null)
{
new CultureInfo(culture);
}
// Add to the column list,
string columnList = p.GetValue("index_column_list", "");
columnList = AddToColumnSet(columnName, columnList);
p.SetValue("index_column_list", columnList);
// Set the index property,
p.SetValue(columnName + ".index", true);
if (culture != null)
{
p.SetValue(columnName + ".culture", culture);
}
// Build the index,
IIndexedObjectComparer <string> indexComparer = GetIndexComparerFor(columnName, columnid);
BuildIndex(columnid, indexComparer);
cachedIndexList = null;
// Add this event to the transaction log,
AddTransactionEvent("addIndex", columnName);
++currentVersion;
}
internal DbIndex(DbTable table, long tableVersion, IIndexedObjectComparer <string> collator, long columnid, IIndex index, long start, long end)
{
this.table = table;
this.tableVersion = tableVersion;
this.collator = collator;
this.columnid = columnid;
this.index = index;
if (start <= end)
{
this.start = start;
this.end = end;
}
else
{
this.start = start;
this.end = start;
}
}
private void BuildIndex(long columnid, IIndexedObjectComparer <string> indexComparer)
{
// Get the index object
IDataFile df = GetDataFile(GetIndexIdKey(columnid));
// Get the index and clear it,
SortedIndex index = new SortedIndex(df);
index.Clear();
// For each row in this table,
foreach (DbRow row in this)
{
// Get the column value and the rowid
string columnValue = row.GetValue(columnid);
long rowid = row.RowId;
// Add it into the index,
index.Insert(columnValue, rowid, indexComparer);
}
// Done.
}
internal DbIndex(DbTable table, long tableVersion, IIndexedObjectComparer <string> collator, long columnid, IIndex index)
: this(table, tableVersion, collator, columnid, index, 0, index.Count)
{
}
