public static int Delete(this IMutableTable table, ITable other, int limit)
{
List<int> rowSet = new List<int>(other.RowCount);
var e = other.GetEnumerator();
while (e.MoveNext()) {
rowSet.Add(e.Current.RowId.RowNumber);
}
// HACKY: Find the first column of this table in the search table. This
// will allow us to generate a row set of only the rows in the search
// table.
int firstColumn = other.IndexOfColumn(table.GetResolvedColumnName(0));
if (firstColumn == -1)
throw new DatabaseSystemException("Search table does not contain any reference to table being deleted from");
// Generate a row set that is in this tables domain.
var rowsToDelete = other.ResolveRows(firstColumn, rowSet, table).ToList();
// row_set may contain duplicate row indices, therefore we must sort so
// any duplicates are grouped and therefore easier to find.
rowSet.Sort();
// If limit less than zero then limit is whole set.
if (limit < 0)
limit = Int32.MaxValue;
// Remove each row in row set in turn. Make sure we don't remove the
// same row index twice.
int len = System.Math.Min(rowsToDelete.Count, limit);
int lastRemoved = -1;
int removeCount = 0;
for (int i = 0; i < len; ++i) {
int toRemove = rowsToDelete[i];
if (toRemove < lastRemoved)
throw new DatabaseSystemException("Internal error: row sorting error or row set not in the range > 0");
if (toRemove != lastRemoved) {
table.RemoveRow(toRemove);
lastRemoved = toRemove;
++removeCount;
}
}
if (removeCount > 0)
// Perform a referential integrity check on any changes to the table.
table.AssertConstraints();
return removeCount;
}
public static int Update(this IMutableTable mutableTable, IQueryContext context, ITable table,
IEnumerable<SqlAssignExpression> assignList, int limit)
{
// Get the rows from the input table.
var rowSet = new List<int>();
var e = table.GetEnumerator();
while (e.MoveNext()) {
rowSet.Add(e.Current.RowId.RowNumber);
}
// HACKY: Find the first column of this table in the search table. This
// will allow us to generate a row set of only the rows in the search
// table.
int firstColumn = table.FindColumn(mutableTable.GetResolvedColumnName(0));
if (firstColumn == -1)
throw new InvalidOperationException("Search table does not contain any " +
"reference to table being updated from");
// Convert the row_set to this table's domain.
rowSet = table.ResolveRows(firstColumn, rowSet, mutableTable).ToList();
// NOTE: Assume there's no duplicate rows.
// If limit less than zero then limit is whole set.
if (limit < 0)
limit = Int32.MaxValue;
// Update each row in row set in turn up to the limit.
int len = System.Math.Min(rowSet.Count, limit);
int updateCount = 0;
for (int i = 0; i < len; ++i) {
int toUpdate = rowSet[i];
// Make a row object from this row (plus keep the original intact
// in case we need to roll back to it).
var row = mutableTable.GetRow(toUpdate);
row.SetFromTable();
// Run each assignment on the row.
foreach (var assignment in assignList) {
row.EvaluateAssignment(assignment, context);
}
// Update the row
mutableTable.UpdateRow(row);
++updateCount;
}
if (updateCount > 0)
// Perform a referential integrity check on any changes to the table.
mutableTable.AssertConstraints();
return updateCount;
}
