/// <summary>
/// returns a <see cref="ValuedColumn"/> parsed from <paramref name="valuedColumnXmlNode"/>.
/// </summary>
/// <param name="valuedColumnXmlNode"></param>
/// <returns>
/// <see cref="ValuedColumn"/> parsed from <paramref name="valuedColumnXmlNode"/>
/// </returns>
/// <exception cref="MissingAttributeException">
/// <seealso cref="XmlNodeExtensionMethods.GetAttributeValue(XmlNode, string)"/>
/// </exception>
/// <exception cref="MissingNodeException">
/// <seealso cref="XmlNodeExtensionMethods.GetNodes(XmlNode, string)"/>
/// </exception>
public static ValuedColumn Parse(XmlNode valuedColumnXmlNode)
{
try
{
string columnName = valuedColumnXmlNode.GetAttributeValue("name");
object columnValue = valuedColumnXmlNode.GetNodes("value")[0].FirstChild.Value;
ValuedColumn valuedColumn = new ValuedColumn(columnName, columnValue);
return(valuedColumn);
}
catch (Exception exception)
{
if (
exception is XmlNodeMissingAttributeException ||
exception is XmlNodeMissingNodeException) // ValuedColumn parse failed
{
throw new ValuedColumnParseException(null, exception);
}
else // unhandled exception
{
throw exception;
}
}
}
protected override string BuildQueryString()
{
StringBuilder queryStringBuilder = new StringBuilder();
// append command header
queryStringBuilder.AppendFormat("UPDATE {0} SET ", this.TableName);
// append ValuedColumns names and new values
for (int i = 0; i < valuedColumns.Length; i++)
{
ValuedColumn valuedColumn = valuedColumns[i];
queryStringBuilder.AppendFormat("{0} = '{1}'", valuedColumn.Name, valuedColumn.Value);
// append seperator
if (i < valuedColumns.Length - 1)
{
queryStringBuilder.Append(", ");
}
}
// append condition
if (queryCondition != null)
{
queryStringBuilder.AppendFormat(" WHERE {0}", this.QueryCondition.ExpressionString);
}
return(queryStringBuilder.ToString());
}
/// <summary>
/// parses <see cref="InsertQuery"/> having <paramref name="tableName"/> from
/// <paramref name="rowDataXmlNode"/>.
/// </summary>
/// <param name="rowDataXmlNode"></param>
/// <param name="tableName"></param>
/// <returns>
/// <see cref="InsertQuery"/> having <paramref name="tableName"/> parsed from
/// <paramref name="rowDataXmlNode"/>
/// </returns>
/// <exception cref="InsertQueryParseException">
/// thrown if <see cref="InsertQuery"/> parse failed
/// </exception>
public static InsertQuery Parse(XmlNode rowDataXmlNode, string tableName)
{
try
{
// get ValuedColumns
XmlNodeList valuedColumnsXmlNodeList = rowDataXmlNode.GetNodes("column");
// number of specified columns might be zero (?)
ValuedColumn[] valuedColumns = new ValuedColumn[valuedColumnsXmlNodeList.Count];
for (int i = 0; i < valuedColumnsXmlNodeList.Count; i++)
{
XmlNode valuedColumnXmlNode = valuedColumnsXmlNodeList[0];
valuedColumns[i] = ValuedColumn.Parse(valuedColumnXmlNode);
}
InsertQuery insertQuery = new InsertQuery(tableName, valuedColumns);
return(insertQuery);
}
catch (XmlNodeMissingAttributeException xmlNodeMissingAttributeException)
{
throw new InsertQueryParseException(xmlNodeMissingAttributeException);
}
}
/// <summary>
/// returns <see cref="ValuedColumn"/>, based on <paramref name="queryType"/>,
/// corresponding to the id of the triggered row in <paramref name="auditedTableSchema"/>.
/// </summary>
/// <remarks>
/// <see cref="ValuedColumn"/> value might reference the old / new row id,
/// before / after the triggering query took place (i.e (old/new).columnName),
/// or the last inserted row id in audited table.
/// </remarks>
/// <param name="auditedTableSchema"></param>
/// <param name="auditTableSchema"></param>
/// <param name="queryType"></param>
/// <returns>
/// <see cref="ValuedColumn"/>, based on <paramref name="queryType"/>,
/// corresponding to the id of the triggered row in <paramref name="auditedTableSchema"/>.
/// </returns>
private static ValuedColumn getAuditedTableTriggeredRowIdValuedColumn(
TableSchema auditedTableSchema,
TableSchema auditTableSchema,
Query.eQueryType queryType)
{
ValuedColumn auditedTableTriggeredRowIdValuedColumn = null;
// name of column (in audit table) containing audited table triggered row id
string columnName = auditTableSchema.ColumnSchemas
[AuditTableStructure.AUDITED_TABLE_ROW_ID_COLUMN_INDEX].Name;
if (queryType == Query.eQueryType.Insert) // get the ID the row got after being inserted
{
object columnValue = new FunctionTableColumn(
FunctionTableColumn.eFunctionType.LastInsertRowid);
auditedTableTriggeredRowIdValuedColumn = new ValuedColumn(columnName, columnValue);
}
else if (queryType == Query.eQueryType.Update || queryType == Query.eQueryType.Delete)
{
// get the id the row had before being updated / deleted
auditedTableTriggeredRowIdValuedColumn = new TriggerValuedColumn(
columnName,
auditedTableSchema.PrimaryKeyColumnSchema.Name,
TriggerValuedColumn.ValueExpression.eTime.Old);
}
return(auditedTableTriggeredRowIdValuedColumn);
}
/// <summary>
/// parses an array of <see cref="ValuedColumn"/>s, each having a corresponding
/// name and value from
/// <paramref name="columnNames"/> and <paramref name="columnValues"/>
/// </summary>
/// <param name="columnNames"></param>
/// <param name="columnValues"></param>
/// <returns>
/// array of <see cref="ValuedColumn"/>s, each having a corresponding
/// name and value from
/// <paramref name="columnNames"/> and <paramref name="columnValues"/>
/// </returns>
/// <exception cref="NamesAndValuesCountMismatchException">
/// <seealso cref="assertColumnNamesAndValuesCountMatches(IList{string}, IList{object})"/>
/// </exception>
public static ValuedColumn[] Parse(IList <string> columnNames, IList <object> columnValues)
{
assertColumnNamesAndValuesCountMatches(columnNames, columnValues);
ValuedColumn[] parsedValuedColumns = new ValuedColumn[columnNames.Count];
for (int i = 0; i < parsedValuedColumns.Length; i++)
{
parsedValuedColumns[i] = new ValuedColumn(columnNames[i], columnValues[i]);
}
return(parsedValuedColumns);
}
/// <summary>
/// appends a single insert value tuple to <paramref name="queryStringBuilder"/>.
/// </summary>
/// <param name="insertQuery"></param>
/// <param name="queryStringBuilder"></param>
private static void appendInsertQuery(
InsertQuery insertQuery,
StringBuilder queryStringBuilder)
{
queryStringBuilder.Append("(");
ValuedColumn[] valuedColumns = insertQuery.ValuedColumns;
for (int i = 0; i < valuedColumns.Length; i++)
{
ValuedColumn valuedColumn = valuedColumns[i];
queryStringBuilder.AppendFormat("'{0}'", valuedColumn.Value);
if (i < valuedColumns.Length - 1)
{
queryStringBuilder.Append(", ");
}
}
queryStringBuilder.Append(")");
}
/// <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);
}
