/// <summary>
/// returns undo <see cref="Query"/> array corresponding to queries performed on
/// <paramref name="auditedTableName"/>, where the i'th undo <see cref="Query"/> in result
/// corresponds the i'th row in <paramref name="auditTableResultSet"/>.
/// </summary>
/// <seealso cref="getUndoQuery(ResultSet.Row, string, Dictionary{long, Query.eQueryType})"/>
/// <param name="auditTableResultSet"></param>
/// <param name="auditedTableName"></param>
/// <param name="queryTypeIdToQueryType"></param>
/// <returns>
/// undo <see cref="Query"/> array corresponding to queries performed on
/// <paramref name="auditedTableName"/>, where the i'th undo <see cref="Query"/> in result
/// corresponds the i'th row in <paramref name="auditTableResultSet"/>
/// </returns>
/// <exception cref="UnsupportedAuditQueryTypeException">
/// <seealso cref="getUndoQuery(ResultSet.Row, string, Dictionary{long, Query.eQueryType})"/>
/// </exception>
internal static WriteQuery[] GetAuditTableUndoWriteQueries(
ResultSet auditTableResultSet,
string auditedTableName,
Dictionary <long, Query.eQueryType> queryTypeIdToQueryType)
{
WriteQuery[] undoQueries = new WriteQuery[auditTableResultSet.RowCount];
for (int i = 0; i < auditTableResultSet.RowCount; i++)
{
ResultSet.Row auditTableRow = auditTableResultSet.Rows[i];
WriteQuery undoQuery = getUndoQuery(
auditTableRow,
auditedTableName,
queryTypeIdToQueryType);
undoQueries[i] = undoQuery;
}
return(undoQueries);
}
/// <summary>
/// returns undo <see cref="Query"/> corresponding to query performed on
/// <paramref name="auditedTableName"/>, where <paramref name="auditTableRow"/> contains
/// the data required to undo a single row in <paramref name="auditedTableName"/>,
/// which was affected by the query.
/// </summary>
/// <param name="auditTableRow"></param>
/// <param name="auditedTableName"></param>
/// <param name="queryTypeIdToQueryType"></param>
/// <returns>
/// undo <see cref="Query"/> corresponding to query performed on
/// <paramref name="auditedTableName"/>, where <paramref name="auditTableRow"/> contains
/// the data required to undo a single row in <paramref name="auditedTableName"/>,
/// which was affected by the query
/// </returns>
/// <exception cref="UnsupportedAuditQueryTypeException">
/// thrown if <see cref="Query.eQueryType"/> specified in <paramref name="auditTableRow"/>
/// is not supported for audit
/// </exception>
private static WriteQuery getUndoQuery(
ResultSet.Row auditTableRow,
string auditedTableName,
Dictionary <long, Query.eQueryType> queryTypeIdToQueryType)
{
WriteQuery undoQuery;
// type of query that was originally performed on audited table
long queryTypeId = auditTableRow.GetColumnValue <long>(
AuditTableStructure.QUERY_ID_COLUMN_INDEX);
Query.eQueryType queryType = queryTypeIdToQueryType[queryTypeId];
// value of _id column of modified row in audit table
long auditedTableRowId = auditTableRow.GetColumnValue <long>(
AuditTableStructure.AUDITED_TABLE_ROW_ID_COLUMN_INDEX);
// get undo query based on query type
if (queryType == Query.eQueryType.Insert)
{
undoQuery = new DeleteQuery(
auditedTableName,
new BasicCondition(
new ValuedTableColumn(
DatabaseStructure.ID_COLUMN_NAME,
auditedTableName,
auditedTableRowId),
BasicCondition.eOperatorType.Equal
)
);
}
else if (queryType == Query.eQueryType.Update || queryType == Query.eQueryType.Delete)
{
// ValuedColumn of _id column of modified row in audited table
ArrayRange <ValuedColumn> auditedTableRowIdArrayRange =
new ArrayRange <ValuedColumn>(
new ValuedColumn(DatabaseStructure.ID_COLUMN_NAME, auditedTableRowId)
);
// ValueColumn of columns other than _id of modified row in audited table
ArrayRange <ValuedColumn> auditedTableRowValuesArrayRange =
new ArrayRange <ValuedColumn>(
ValuedColumn.Parse(auditTableRow.ColumnNames, auditTableRow.ColumnValues),
AuditTableStructure.AUDITED_TABLE_DATA_COLUMNS_START_INDEX);
// unified ValuedColumn list for undo query
List <ValuedColumn> queryValuedColumns
= ListUtils.ListFromArrayRanges(
auditedTableRowIdArrayRange,
auditedTableRowValuesArrayRange);
if (queryType == Query.eQueryType.Update)
{
undoQuery = new UpdateQuery(
auditedTableName,
queryValuedColumns,
new BasicCondition(
new ValuedTableColumn(
DatabaseStructure.ID_COLUMN_NAME,
auditedTableName,
auditedTableRowId),
BasicCondition.eOperatorType.Equal
)
);
}
else // queryType == Query.eQueryType.Delete
{
undoQuery = new InsertQuery(auditedTableName, queryValuedColumns);
}
}
else
{
throw new UnsupportedAuditQueryTypeException(queryType);
}
return(undoQuery);
}