public int update() {
		if (updateColumnDeclarations.size() == 0) {
			throw new IciqlException("Missing set or increment call.");
		}
		SQLStatement stat = new SQLStatement(db);
		stat.appendSQL("UPDATE ");
		from.appendSQL(stat);
		stat.appendSQL(" SET ");
		int i = 0;
		for (UpdateColumn declaration : updateColumnDeclarations) {
			if (i++ > 0) {
				stat.appendSQL(", ");
			}
			declaration.appendSQL(stat);
		}
		appendWhere(stat);
		IciqlLogger.update(stat.getSQL());
		return stat.executeUpdate();
	}