示例#1
0
        /// <summary>
        /// Generates a statement to query the values of the complex <see cref="QueryAttribute"/>.
        /// </summary>
        /// <param name="valueAlias">Alias for the value column.</param>
        /// <param name="mediaItemIdAlias">Alias for the ID of the media item to which the value belongs.</param>
        /// <param name="statementStr">Statement which was built by this method.</param>
        /// <param name="bindVars">Bind variables to be inserted into placeholders in the returned <paramref name="statementStr"/>.</param>
        public void GenerateSqlStatement(out string mediaItemIdAlias, out string valueAlias,
                                         out string statementStr, out IList <BindVar> bindVars)
        {
            Namespace        ns          = new Namespace();
            BindVarNamespace bvNamespace = new BindVarNamespace();

            // Contains a mapping of each queried (=selected or filtered) attribute to its request attribute instance
            // data (which holds its requested query table instance)
            IDictionary <QueryAttribute, RequestedAttribute> requestedAttributes = new Dictionary <QueryAttribute, RequestedAttribute>();

            // Dictionary containing as key the requested MIAM instance OR attribute specification of cardinality MTO,
            // mapped to the table query data to request its contents.
            IDictionary <object, TableQueryData> tableQueries = new Dictionary <object, TableQueryData>();

            // Contains the same tables as the tableQueries variable, but in order and enriched with table join data
            IList <TableJoin> tableJoins = new List <TableJoin>();

            // First create the request table query data for the external attribute table, which contains the foreign key
            // to the MIA ID, and the request attribute for that MIA ID.
            // We'll need the requested attribute as join attribute soon.
            TableQueryData     mainJoinTableQuery;
            RequestedAttribute miaIdAttribute;
            RequestedAttribute valueAttribute;
            RequestedAttribute orderAttribute;

            // Build main join table
            switch (_queryAttribute.Cardinality)
            {
            case Cardinality.OneToMany:
                mainJoinTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeTableName(_queryAttribute));
                miaIdAttribute     = new RequestedAttribute(mainJoinTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME);
                valueAttribute     = new RequestedAttribute(mainJoinTableQuery, MIA_Management.COLL_ATTR_VALUE_COL_NAME);
                orderAttribute     = new RequestedAttribute(mainJoinTableQuery, MIA_Management.COLL_ATTR_VALUE_ORDER_COL_NAME);
                break;

            case Cardinality.ManyToMany:
                mainJoinTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeNMTableName(_queryAttribute));
                miaIdAttribute     = new RequestedAttribute(mainJoinTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME);
                TableQueryData collAttrTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeTableName(_queryAttribute));
                tableJoins.Add(new TableJoin("INNER JOIN", collAttrTableQuery,
                                             new RequestedAttribute(mainJoinTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME),
                                             new RequestedAttribute(collAttrTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME)));
                valueAttribute = new RequestedAttribute(collAttrTableQuery, MIA_Management.COLL_ATTR_VALUE_COL_NAME);
                orderAttribute = new RequestedAttribute(mainJoinTableQuery, MIA_Management.COLL_ATTR_VALUE_ORDER_COL_NAME);
                break;

            default:
                throw new IllegalCallException("Media item aspect attributes of cardinality '{0}' cannot be requested via the {1}",
                                               _queryAttribute.Cardinality, GetType().Name);
            }
            tableJoins.Insert(0, new TableJoin("INNER JOIN", mainJoinTableQuery, null, null)); // The first table join doesn't need the join attributes - see below

            // Ensure that the tables for all necessary MIAs are requested first (INNER JOIN)
            foreach (MediaItemAspectMetadata miaType in _necessaryRequestedMIAs)
            {
                if (tableQueries.ContainsKey(miaType))
                {
                    // We only come here if miaType is the MIA of the requested attribute itself or if it was already queried as necessary MIA, so optimize redundant entry
                    continue;
                }
                //If any MultipleMediaItemAspect are requested, the joining below will cause duplicate values
                //TableQueryData tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
                //tableJoins.Add(new TableJoin("INNER JOIN", tqd, new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
            }

            CompiledFilter compiledFilter = new CompiledFilter(_miaManagement, _filter, _subqueryFilter, ns, bvNamespace, miaIdAttribute.GetQualifiedName(ns), tableJoins);

            // Build table query data for each Inline attribute which is part of a filter
            // + compile query attribute
            foreach (QueryAttribute attr in compiledFilter.RequiredAttributes)
            {
                if (attr.Attr.Cardinality != Cardinality.Inline && attr.Attr.Cardinality != Cardinality.ManyToOne)
                {
                    continue;
                }
                // Tables of Inline and MTO attributes, which are part of a filter, are joined with main table
                RequestedAttribute ra;
                RequestSimpleAttribute(attr, tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes,
                                       null, miaIdAttribute, out ra);
            }
            StringBuilder result = new StringBuilder("SELECT ");

            // Append MIA ID attribute only if no DISTINCT query is made
            result.Append(_selectProjectionFunction == null ?
                          miaIdAttribute.GetDeclarationWithAlias(ns, out mediaItemIdAlias) :
                          miaIdAttribute.GetDeclarationWithAlias(ns, _selectProjectionFunction, out mediaItemIdAlias));
            result.Append(", ");

            // Selected attributes
            result.Append(valueAttribute.GetDeclarationWithAlias(ns, out valueAlias));

            string whereStr = compiledFilter.CreateSqlFilterCondition(ns, requestedAttributes, out bindVars);

            result.Append(" FROM ");

            bool firstJoinTable = true;

            // Other joined tables
            foreach (TableJoin tableJoin in tableJoins)
            {
                if (firstJoinTable)
                {
                    result.Append(tableJoin.JoinedTable.GetDeclarationWithAlias(ns));
                    firstJoinTable = false;
                }
                else
                {
                    result.Append(tableJoin.GetJoinDeclaration(ns));
                }
                result.Append(' ');
            }

            if (!string.IsNullOrEmpty(whereStr))
            {
                result.Append("WHERE ");
                result.Append(whereStr);
            }

            if (orderAttribute != null)
            {
                result.Append(" ORDER BY ");
                result.Append(orderAttribute.GetQualifiedName(ns));
            }

            statementStr = result.ToString();
        }
示例#2
0
        /// <summary>
        /// Generates a statement to query the distinct values of the complex <see cref="QueryAttribute"/>, together with their
        /// occurence count.
        /// </summary>
        /// <param name="queryAttributeFilter">Additional filter which is defined on the <see cref="QueryAttribute"/>.
        /// That filter COULD be part of the <see cref="Filter"/> but this method can highly optimize a filter on the
        /// query attribute, so a filter on that attribute should be given in this parameter and should not be part of the <see cref="Filter"/>.
        /// </param>
        /// <param name="valueAlias">Alias for the value column.</param>
        /// <param name="groupSizeAlias">Alias for the column containing the number of items in each group.</param>
        /// <param name="statementStr">Statement which was built by this method.</param>
        /// <param name="bindVars">Bind variables to be inserted into placeholders in the returned <paramref name="statementStr"/>.</param>
        public void GenerateSqlGroupByStatement(IAttributeFilter queryAttributeFilter,
                                                out string valueAlias, out string groupSizeAlias, out string statementStr, out IList <BindVar> bindVars)
        {
            Namespace        ns          = new Namespace();
            BindVarNamespace bvNamespace = new BindVarNamespace();

            // Contains a mapping of each queried (=selected or filtered) attribute to its request attribute instance
            // data (which holds its requested query table instance)
            IDictionary <QueryAttribute, RequestedAttribute> requestedAttributes = new Dictionary <QueryAttribute, RequestedAttribute>();

            // Dictionary containing as key the requested MIAM instance OR attribute specification of cardinality MTO,
            // mapped to the table query data to request its contents.
            IDictionary <object, TableQueryData> tableQueries = new Dictionary <object, TableQueryData>();

            // Contains the same tables as the tableQueries variable, but in order and enriched with table join data
            IList <TableJoin> tableJoins = new List <TableJoin>();

            // First create the request table query data for the MIA main table and the request attribute for the MIA ID.
            // We'll need the requested attribute as join attribute soon.
            MediaItemAspectMetadata queryMIAM     = _queryAttribute.ParentMIAM;
            TableQueryData          miaTableQuery = new TableQueryData(_miaManagement.GetMIATableName(queryMIAM));

            tableQueries.Add(queryMIAM, miaTableQuery);

            RequestedAttribute miaIdAttribute = new RequestedAttribute(miaTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME);

            // Ensure that the tables for all necessary MIAs are requested first (INNER JOIN)
            foreach (MediaItemAspectMetadata miaType in _necessaryRequestedMIAs)
            {
                TableQueryData tqd;
                if (!tableQueries.TryGetValue(miaType, out tqd))
                {
                    tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
                }
                if (miaType != queryMIAM)
                {
                    tableJoins.Add(new TableJoin("INNER JOIN", tqd,
                                                 new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
                }
            }

            CompiledFilter compiledFilter = new CompiledFilter(_miaManagement, _filter, _subqueryFilter, ns, bvNamespace, miaIdAttribute.GetQualifiedName(ns), tableJoins);

            // Build table query data for each Inline attribute which is part of a filter
            // + compile query attribute
            foreach (QueryAttribute attr in compiledFilter.RequiredAttributes)
            {
                if (attr.Attr.Cardinality != Cardinality.Inline && attr.Attr.Cardinality != Cardinality.ManyToOne)
                {
                    continue;
                }
                // Tables of Inline and MTO attributes, which are part of a filter, are joined with main table
                RequestedAttribute ra;
                RequestSimpleAttribute(attr, tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes,
                                       null, miaIdAttribute, out ra);
            }

            TableQueryData     joinTableQuery;
            RequestedAttribute valueAttribute;

            // Build join table for value attribute
            switch (_queryAttribute.Cardinality)
            {
            case Cardinality.OneToMany:
                joinTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeTableName(_queryAttribute));
                tableJoins.Add(new TableJoin("LEFT OUTER JOIN", joinTableQuery,
                                             new RequestedAttribute(joinTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME),
                                             new RequestedAttribute(miaTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME)));
                valueAttribute = new RequestedAttribute(joinTableQuery, MIA_Management.COLL_ATTR_VALUE_COL_NAME);
                break;

            case Cardinality.ManyToMany:
                joinTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeNMTableName(_queryAttribute));
                tableJoins.Add(new TableJoin("LEFT OUTER JOIN", joinTableQuery,
                                             new RequestedAttribute(joinTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME),
                                             new RequestedAttribute(miaTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME)));
                TableQueryData collAttrTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeTableName(_queryAttribute));
                tableJoins.Add(new TableJoin("LEFT OUTER JOIN", collAttrTableQuery,
                                             new RequestedAttribute(joinTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME),
                                             new RequestedAttribute(collAttrTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME)));
                valueAttribute = new RequestedAttribute(collAttrTableQuery, MIA_Management.COLL_ATTR_VALUE_COL_NAME);
                break;

            default:
                throw new IllegalCallException("Media item aspect attributes of cardinality '{0}' cannot be requested via the {1}",
                                               _queryAttribute.Cardinality, GetType().Name);
            }

            // Selected attributes
            string valueDeclaration = _selectProjectionFunction == null?
                                      valueAttribute.GetDeclarationWithAlias(ns, out valueAlias) :
                                          valueAttribute.GetDeclarationWithAlias(ns, _selectProjectionFunction, out valueAlias);

            groupSizeAlias = "C";
            StringBuilder result = new StringBuilder("SELECT COUNT(V.ID) ");

            result.Append(groupSizeAlias);
            result.Append(", V.");
            result.Append(valueAlias);
            result.Append(" FROM (");
            result.Append("SELECT DISTINCT ");
            result.Append(miaIdAttribute.GetQualifiedName(ns));
            result.Append(" ID, ");
            result.Append(valueDeclaration);

            string whereStr = compiledFilter.CreateSqlFilterCondition(ns, requestedAttributes, out bindVars);

            result.Append(" FROM ");

            // Always request the mia table
            result.Append(miaTableQuery.GetDeclarationWithAlias(ns));
            result.Append(' ');

            // Other joined tables
            foreach (TableJoin tableJoin in tableJoins)
            {
                result.Append(tableJoin.GetJoinDeclaration(ns));
                result.Append(' ');
            }

            if (!string.IsNullOrEmpty(whereStr) || queryAttributeFilter != null)
            {
                result.Append("WHERE ");
                IList <string> filters = new List <string>(2);
                if (!string.IsNullOrEmpty(whereStr))
                {
                    filters.Add(whereStr);
                }
                if (queryAttributeFilter != null)
                {
                    IList <object> resultParts = new List <object>();
                    CompiledFilter.BuildAttributeFilterExpression(queryAttributeFilter, valueAttribute.GetQualifiedName(ns), bvNamespace,
                                                                  resultParts, bindVars);
                    string filterStr = CompiledFilter.CreateSimpleSqlFilterCondition(ns, resultParts, requestedAttributes);
                    filters.Add(filterStr);
                }
                result.Append(StringUtils.Join(" AND ", filters));
            }

            result.Append(") V GROUP BY V.");
            result.Append(valueAlias);

            statementStr = result.ToString();
        }
        protected void GenerateSqlStatement(bool groupByValues,
                                            IDictionary <MediaItemAspectMetadata, string> miamAliases,
                                            out string mediaItemIdOrGroupSizeAlias,
                                            out IDictionary <QueryAttribute, string> attributeAliases,
                                            out string statementStr, out IList <BindVar> bindVars)
        {
            Namespace        ns          = new Namespace();
            BindVarNamespace bvNamespace = new BindVarNamespace();

            // Contains a mapping of each queried (=selected or filtered) attribute to its request attribute instance
            // data (which holds its requested query table instance)
            IDictionary <QueryAttribute, RequestedAttribute> requestedAttributes = new Dictionary <QueryAttribute, RequestedAttribute>();

            attributeAliases = new Dictionary <QueryAttribute, string>();

            // Contains a list of qualified attribute names for all select attributes - needed for GROUP BY-expressions
            ICollection <string> qualifiedGroupByAliases = new List <string>();

            // Contains a list of compiled select attribute declarations. We need this in a separate list (in contrast to using
            // the selectAttributes list together with the compiledAttributes map) because it might be the case that
            // an attribute is requested twice. In that rare case, we need a new alias name for it.
            IList <string> selectAttributeDeclarations = new List <string>();

            // Dictionary containing as key the requested MIAM instance OR attribute specification of cardinality MTO,
            // mapped to the table query data to request its contents.
            IDictionary <object, TableQueryData> tableQueries = new Dictionary <object, TableQueryData>();

            // Contains the same tables as the tableQueries variable, but in order and enriched with table join data
            IList <TableJoin> tableJoins = new List <TableJoin>();

            // Contains all table query data for MIA type tables
            IDictionary <MediaItemAspectMetadata, TableQueryData> miaTypeTableQueries = new Dictionary <MediaItemAspectMetadata, TableQueryData>();

            // Albert, 2012-01-29: Optimized query, don't join with media items table, if we have necessary requested MIAs. In that case,
            // we can use one of their media item ids.
            //// First create the request table query data for the MIA main table and the request attribute for the MIA ID.
            //// We'll need the requested attribute as join attribute soon.
            //TableQueryData miaTableQuery = new TableQueryData(MediaLibrary_SubSchema.MEDIA_ITEMS_TABLE_NAME);
            //RequestedAttribute miaIdAttribute = new RequestedAttribute(miaTableQuery, MediaLibrary_SubSchema.MEDIA_ITEMS_ITEM_ID_COL_NAME);

            RequestedAttribute miaIdAttribute = null; // Lazy initialized below

            // Contains CompiledSortInformation instances for each sort information instance
            IList <CompiledSortInformation> compiledSortInformation = null;

            List <BindVar> sqlVars = new List <BindVar>();

            // Ensure that the tables for all necessary MIAs are requested first (INNER JOIN)
            foreach (MediaItemAspectMetadata miaType in _necessaryRequestedMIAs)
            {
                if (miaType.IsTransientAspect)
                {
                    continue;
                }
                if (tableQueries.ContainsKey(miaType))
                {
                    // We only come here if miaType was already queried as necessary MIA, so optimize redundant entry
                    continue;
                }

                TableQueryData tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
                miaTypeTableQueries.Add(miaType, tqd);
                RequestedAttribute ra;
                // The first table join has invalid join attributes because miaIdAttribute is still null - but only the join table attribute is necessary
                // for the the first table - see below
                tableJoins.Add(new TableJoin("INNER JOIN", tqd,
                                             ra = new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
                if (miaIdAttribute == null)
                {
                    miaIdAttribute = ra;
                }
            }

            if (miaIdAttribute == null)
            {                                                                           // If we didn't request any necessary MIA types, we have to add an artificial table for the miaIdAttribute
                TableQueryData miaTableQuery = new TableQueryData(MediaLibrary_SubSchema.MEDIA_ITEMS_TABLE_NAME);
                tableJoins.Add(new TableJoin("INNER JOIN", miaTableQuery, null, null)); // First table join has invalid join attributes - not needed for first table
                miaIdAttribute = new RequestedAttribute(miaTableQuery, MediaLibrary_SubSchema.MEDIA_ITEMS_ITEM_ID_COL_NAME);
            }

            // Ensure that the tables for all optional MIAs are requested first (LEFT OUTER JOIN)
            // That is necessary to make empty optional MIA types available in the result
            foreach (MediaItemAspectMetadata miaType in _optionalRequestedMIAs)
            {
                if (miaType.IsTransientAspect)
                {
                    continue;
                }
                if (tableQueries.ContainsKey(miaType))
                {
                    // We only come here if miaType was already queried as necessary or optional MIA, so optimize redundant entry
                    continue;
                }
                TableQueryData tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
                miaTypeTableQueries.Add(miaType, tqd);
                tableJoins.Add(new TableJoin("LEFT OUTER JOIN", tqd,
                                             new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
            }

            // Build table query data for each selected Inline and MTO attribute
            // + select query attribute
            // + add alias to selectAttributeDeclarations
            foreach (QueryAttribute attr in _selectAttributes)
            {
                if (attr.Attr.ParentMIAM.IsTransientAspect)
                {
                    continue;
                }
                RequestedAttribute ra;
                RequestSimpleAttribute(attr, tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes, miaTypeTableQueries,
                                       miaIdAttribute, out ra);
                string alias;
                selectAttributeDeclarations.Add(_selectProjectionFunction == null ?
                                                ra.GetDeclarationWithAlias(ns, out alias) :
                                                ra.GetDeclarationWithAlias(ns, _selectProjectionFunction, out alias));
                attributeAliases.Add(attr, alias);
                qualifiedGroupByAliases.Add(ra.GetAlias(ns));
            }

            CompiledFilter compiledFilter = CreateCompiledFilter(ns, bvNamespace, miaIdAttribute.GetQualifiedName(ns), tableJoins);

            // Build table query data for each Inline attribute which is part of a filter
            // + compile query attribute
            foreach (QueryAttribute attr in compiledFilter.RequiredAttributes)
            {
                if (attr.Attr.ParentMIAM.IsTransientAspect)
                {
                    continue;
                }
                if (attr.Attr.Cardinality != Cardinality.Inline && attr.Attr.Cardinality != Cardinality.ManyToOne)
                {
                    continue;
                }
                // Tables of Inline and MTO attributes, which are part of a filter, are joined with main table
                RequestedAttribute ra;
                RequestSimpleAttribute(attr, tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes,
                                       miaTypeTableQueries, miaIdAttribute, out ra);
            }
            // Build table query data for each sort attribute
            if (_sortInformation != null)
            {
                compiledSortInformation = new List <CompiledSortInformation>();
                BindVar userVar = null;
                foreach (ISortInformation sortInformation in _sortInformation)
                {
                    AttributeSortInformation attributeSort = sortInformation as AttributeSortInformation;
                    if (attributeSort != null)
                    {
                        if (attributeSort.AttributeType.ParentMIAM.IsTransientAspect)
                        {
                            continue;
                        }
                        MediaItemAspectMetadata.AttributeSpecification attr = attributeSort.AttributeType;
                        if (attr.Cardinality != Cardinality.Inline && attr.Cardinality != Cardinality.ManyToOne)
                        {
                            // Sorting can only be done for Inline and MTO attributes
                            continue;
                        }
                        RequestedAttribute ra;
                        RequestSimpleAttribute(new QueryAttribute(attr), tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes,
                                               miaTypeTableQueries, miaIdAttribute, out ra);
                        compiledSortInformation.Add(new CompiledSortInformation(ra, attributeSort.Direction));
                        continue;
                    }

                    DataSortInformation dataSort = sortInformation as DataSortInformation;
                    if (dataSort != null && _userProfileId.HasValue)
                    {
                        TableQueryData     tqd = new TableQueryData(UserProfileDataManagement.UserProfileDataManagement_SubSchema.USER_MEDIA_ITEM_DATA_TABLE_NAME);
                        RequestedAttribute ra  = new RequestedAttribute(tqd, UserProfileDataManagement.UserProfileDataManagement_SubSchema.USER_DATA_VALUE_COL_NAME);
                        compiledSortInformation.Add(new CompiledSortInformation(ra, dataSort.Direction));

                        if (userVar == null)
                        {
                            userVar = new BindVar("UID", _userProfileId.Value, typeof(Guid));
                            sqlVars.Add(userVar);
                        }
                        TableJoin join = new TableJoin("LEFT OUTER JOIN", tqd, new RequestedAttribute(tqd, UserProfileDataManagement.UserProfileDataManagement_SubSchema.USER_PROFILE_ID_COL_NAME), "@" + userVar.Name);
                        join.AddCondition(new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute);
                        join.AddCondition(new RequestedAttribute(tqd, UserProfileDataManagement.UserProfileDataManagement_SubSchema.USER_DATA_KEY_COL_NAME), $"'{dataSort.UserDataKey}'");
                        tableJoins.Add(join);
                    }
                }
            }
            StringBuilder result = new StringBuilder("SELECT ");

            string groupClause = StringUtils.Join(", ", qualifiedGroupByAliases.Select(alias => "V." + alias));

            if (groupByValues)
            {
                mediaItemIdOrGroupSizeAlias = "C";
                // Create an additional COUNT expression for the MEDIA_ITEMS.MEDIA_ITEM_ID in the GROUP BY-statement
                result.Append("COUNT(V.C) ");
                result.Append(mediaItemIdOrGroupSizeAlias);
                if (!string.IsNullOrWhiteSpace(groupClause))
                {
                    result.Append(", ");
                    result.Append(groupClause);
                }
                result.Append(" FROM (");
                result.Append("SELECT DISTINCT ");
                result.Append(miaIdAttribute.GetQualifiedName(ns));
                result.Append(" C");
            }
            else
            {
                // Append plain attribute MEDIA_ITEMS.MEDIA_ITEM_ID if no GROUP BY-statement is requested
                result.Append(miaIdAttribute.GetDeclarationWithAlias(ns, out mediaItemIdOrGroupSizeAlias));

                // System attributes: Necessary to evaluate if a requested MIA is present for the media item
                foreach (KeyValuePair <MediaItemAspectMetadata, TableQueryData> kvp in miaTypeTableQueries)
                {
                    result.Append(", ");
                    string miamColumn = kvp.Value.GetAlias(ns) + "." + MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME;
                    result.Append(miamColumn);
                    string miamAlias = ns.GetOrCreate(miamColumn, "A");
                    result.Append(" ");
                    result.Append(miamAlias);
                    if (miamAlias != null)
                    {
                        miamAliases.Add(kvp.Key, miamAlias);
                    }
                }
            }

            // Selected attributes
            foreach (string selectAttr in selectAttributeDeclarations)
            {
                result.Append(", ");
                result.Append(selectAttr);
            }

            string whereStr = compiledFilter.CreateSqlFilterCondition(ns, requestedAttributes, out bindVars);

            foreach (BindVar bv in sqlVars)
            {
                bindVars.Add(bv);
            }

            result.Append(" FROM ");

            bool firstJoinTable = true;

            // Other joined tables
            foreach (TableJoin tableJoin in tableJoins)
            {
                if (firstJoinTable)
                {
                    result.Append(tableJoin.JoinedTable.GetDeclarationWithAlias(ns));
                    firstJoinTable = false;
                }
                else
                {
                    result.Append(tableJoin.GetJoinDeclaration(ns));
                }
                result.Append(' ');
            }

            if (!string.IsNullOrEmpty(whereStr))
            {
                result.Append(" WHERE ");
                result.Append(whereStr);
            }
            if (groupByValues)
            {
                result.Append(") V");
                if (qualifiedGroupByAliases.Count > 0)
                {
                    result.Append(" GROUP BY ");
                    result.Append(groupClause);
                }
            }
            else
            {
                if (compiledSortInformation != null && compiledSortInformation.Count > 0)
                {
                    IEnumerable <string> sortCriteria = compiledSortInformation.Select(csi => csi.GetSortDeclaration(ns));
                    result.Append(" ORDER BY ");
                    result.Append(StringUtils.Join(", ", sortCriteria));
                }
            }
            statementStr = result.ToString();
        }
    /// <summary>
    /// Generates a statement to query the distinct values of the complex <see cref="QueryAttribute"/>, together with their
    /// occurence count.
    /// </summary>
    /// <param name="queryAttributeFilter">Additional filter which is defined on the <see cref="QueryAttribute"/>.
    /// That filter COULD be part of the <see cref="Filter"/> but this method can highly optimize a filter on the
    /// query attribute, so a filter on that attribute should be given in this parameter and should not be part of the <see cref="Filter"/>.
    /// </param>
    /// <param name="valueAlias">Alias for the value column.</param>
    /// <param name="groupSizeAlias">Alias for the column containing the number of items in each group.</param>
    /// <param name="statementStr">Statement which was built by this method.</param>
    /// <param name="bindVars">Bind variables to be inserted into placeholders in the returned <paramref name="statementStr"/>.</param>
    public void GenerateSqlGroupByStatement(IAttributeFilter queryAttributeFilter,
        out string valueAlias, out string groupSizeAlias, out string statementStr, out IList<BindVar> bindVars)
    {
      Namespace ns = new Namespace();
      BindVarNamespace bvNamespace = new BindVarNamespace();

      // Contains a mapping of each queried (=selected or filtered) attribute to its request attribute instance
      // data (which holds its requested query table instance)
      IDictionary<QueryAttribute, RequestedAttribute> requestedAttributes = new Dictionary<QueryAttribute, RequestedAttribute>();

      // Dictionary containing as key the requested MIAM instance OR attribute specification of cardinality MTO,
      // mapped to the table query data to request its contents.
      IDictionary<object, TableQueryData> tableQueries = new Dictionary<object, TableQueryData>();

      // Contains the same tables as the tableQueries variable, but in order and enriched with table join data
      IList<TableJoin> tableJoins = new List<TableJoin>();

      // First create the request table query data for the MIA main table and the request attribute for the MIA ID.
      // We'll need the requested attribute as join attribute soon.
      MediaItemAspectMetadata queryMIAM = _queryAttribute.ParentMIAM;
      TableQueryData miaTableQuery = new TableQueryData(_miaManagement.GetMIATableName(queryMIAM));
      tableQueries.Add(queryMIAM, miaTableQuery);

      RequestedAttribute miaIdAttribute = new RequestedAttribute(miaTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME);

      // Ensure that the tables for all necessary MIAs are requested first (INNER JOIN)
      foreach (MediaItemAspectMetadata miaType in _necessaryRequestedMIAs)
      {
        TableQueryData tqd;
        if (!tableQueries.TryGetValue(miaType, out tqd))
          tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
        if (miaType != queryMIAM)
          tableJoins.Add(new TableJoin("INNER JOIN", tqd,
              new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
      }

      CompiledFilter compiledFilter = new CompiledFilter(_miaManagement, _filter, ns, bvNamespace, miaIdAttribute.GetQualifiedName(ns), tableJoins);

      // Build table query data for each Inline attribute which is part of a filter
      // + compile query attribute
      foreach (QueryAttribute attr in compiledFilter.RequiredAttributes)
      {
        if (attr.Attr.Cardinality != Cardinality.Inline && attr.Attr.Cardinality != Cardinality.ManyToOne)
          continue;
        // Tables of Inline and MTO attributes, which are part of a filter, are joined with main table
        RequestedAttribute ra;
        RequestSimpleAttribute(attr, tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes,
            null, miaIdAttribute, out ra);
      }

      TableQueryData joinTableQuery;
      RequestedAttribute valueAttribute;

      // Build join table for value attribute
      switch (_queryAttribute.Cardinality)
      {
        case Cardinality.OneToMany:
          joinTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeTableName(_queryAttribute));
          tableJoins.Add(new TableJoin("LEFT OUTER JOIN", joinTableQuery,
              new RequestedAttribute(joinTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME),
              new RequestedAttribute(miaTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME)));
          valueAttribute = new RequestedAttribute(joinTableQuery, MIA_Management.COLL_ATTR_VALUE_COL_NAME);
          break;
        case Cardinality.ManyToMany:
          joinTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeNMTableName(_queryAttribute));
          tableJoins.Add(new TableJoin("LEFT OUTER JOIN", joinTableQuery,
              new RequestedAttribute(joinTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME),
              new RequestedAttribute(miaTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME)));
          TableQueryData collAttrTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeTableName(_queryAttribute));
          tableJoins.Add(new TableJoin("LEFT OUTER JOIN", collAttrTableQuery,
              new RequestedAttribute(joinTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME),
              new RequestedAttribute(collAttrTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME)));
          valueAttribute = new RequestedAttribute(collAttrTableQuery, MIA_Management.COLL_ATTR_VALUE_COL_NAME);
          break;
        default:
          throw new IllegalCallException("Media item aspect attributes of cardinality '{0}' cannot be requested via the {1}",
              _queryAttribute.Cardinality, GetType().Name);
      }

      // Selected attributes
      string valueDeclaration = _selectProjectionFunction == null ?
          valueAttribute.GetDeclarationWithAlias(ns, out valueAlias) :
          valueAttribute.GetDeclarationWithAlias(ns, _selectProjectionFunction, out valueAlias);
      groupSizeAlias = "C";
      StringBuilder result = new StringBuilder("SELECT COUNT(V.ID) ");
      result.Append(groupSizeAlias);
      result.Append(", V.");
      result.Append(valueAlias);
      result.Append(" FROM (");
      result.Append("SELECT DISTINCT ");
      result.Append(miaIdAttribute.GetQualifiedName(ns));
      result.Append(" ID, ");
      result.Append(valueDeclaration);

      string whereStr = compiledFilter.CreateSqlFilterCondition(ns, requestedAttributes, out bindVars);

      result.Append(" FROM ");

      // Always request the mia table
      result.Append(miaTableQuery.GetDeclarationWithAlias(ns));
      result.Append(' ');

      // Other joined tables
      foreach (TableJoin tableJoin in tableJoins)
      {
        result.Append(tableJoin.GetJoinDeclaration(ns));
        result.Append(' ');
      }

      if (!string.IsNullOrEmpty(whereStr) || queryAttributeFilter != null)
      {
        result.Append("WHERE ");
        IList<string> filters = new List<string>(2);
        if (!string.IsNullOrEmpty(whereStr))
          filters.Add(whereStr);
        if (queryAttributeFilter != null)
        {
          IList<object> resultParts = new List<object>();
          CompiledFilter.BuildAttributeFilterExpression(queryAttributeFilter, valueAttribute.GetQualifiedName(ns), bvNamespace,
              resultParts, bindVars);
          string filterStr = CompiledFilter.CreateSimpleSqlFilterCondition(ns, resultParts, requestedAttributes);
          filters.Add(filterStr);
        }
        result.Append(StringUtils.Join(" AND ", filters));
      }

      result.Append(") V GROUP BY V.");
      result.Append(valueAlias);

      statementStr = result.ToString();
    }
    /// <summary>
    /// Generates a statement to query the values of the complex <see cref="QueryAttribute"/>.
    /// </summary>
    /// <param name="valueAlias">Alias for the value column.</param>
    /// <param name="mediaItemIdAlias">Alias for the ID of the media item to which the value belongs.</param>
    /// <param name="statementStr">Statement which was built by this method.</param>
    /// <param name="bindVars">Bind variables to be inserted into placeholders in the returned <paramref name="statementStr"/>.</param>
    public void GenerateSqlStatement(out string mediaItemIdAlias, out string valueAlias,
        out string statementStr, out IList<BindVar> bindVars)
    {
      Namespace ns = new Namespace();
      BindVarNamespace bvNamespace = new BindVarNamespace();

      // Contains a mapping of each queried (=selected or filtered) attribute to its request attribute instance
      // data (which holds its requested query table instance)
      IDictionary<QueryAttribute, RequestedAttribute> requestedAttributes = new Dictionary<QueryAttribute, RequestedAttribute>();

      // Dictionary containing as key the requested MIAM instance OR attribute specification of cardinality MTO,
      // mapped to the table query data to request its contents.
      IDictionary<object, TableQueryData> tableQueries = new Dictionary<object, TableQueryData>();

      // Contains the same tables as the tableQueries variable, but in order and enriched with table join data
      IList<TableJoin> tableJoins = new List<TableJoin>();

      // First create the request table query data for the external attribute table, which contains the foreign key
      // to the MIA ID, and the request attribute for that MIA ID.
      // We'll need the requested attribute as join attribute soon.
      TableQueryData mainJoinTableQuery;
      RequestedAttribute miaIdAttribute;
      RequestedAttribute valueAttribute;

      // Build main join table
      switch (_queryAttribute.Cardinality)
      {
        case Cardinality.OneToMany:
          mainJoinTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeTableName(_queryAttribute));
          miaIdAttribute = new RequestedAttribute(mainJoinTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME);
          valueAttribute = new RequestedAttribute(mainJoinTableQuery, MIA_Management.COLL_ATTR_VALUE_COL_NAME);
          break;
        case Cardinality.ManyToMany:
          mainJoinTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeNMTableName(_queryAttribute));
          miaIdAttribute = new RequestedAttribute(mainJoinTableQuery, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME);
          TableQueryData collAttrTableQuery = new TableQueryData(_miaManagement.GetMIACollectionAttributeTableName(_queryAttribute));
          tableJoins.Add(new TableJoin("INNER JOIN", collAttrTableQuery,
              new RequestedAttribute(mainJoinTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME),
              new RequestedAttribute(collAttrTableQuery, MIA_Management.FOREIGN_COLL_ATTR_ID_COL_NAME)));
          valueAttribute = new RequestedAttribute(collAttrTableQuery, MIA_Management.COLL_ATTR_VALUE_COL_NAME);
          break;
        default:
          throw new IllegalCallException("Media item aspect attributes of cardinality '{0}' cannot be requested via the {1}",
              _queryAttribute.Cardinality, GetType().Name);
      }
      tableJoins.Insert(0, new TableJoin("INNER JOIN", mainJoinTableQuery, null, null)); // The first table join doesn't need the join attributes - see below

      // Ensure that the tables for all necessary MIAs are requested first (INNER JOIN)
      foreach (MediaItemAspectMetadata miaType in _necessaryRequestedMIAs)
      {
        if (tableQueries.ContainsKey(miaType))
          // We only come here if miaType is the MIA of the requested attribute itself or if it was already queried as necessary MIA, so optimize redundant entry
          continue;
        TableQueryData tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
        tableJoins.Add(new TableJoin("INNER JOIN", tqd,
            new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
      }

      CompiledFilter compiledFilter = new CompiledFilter(_miaManagement, _filter, ns, bvNamespace, miaIdAttribute.GetQualifiedName(ns), tableJoins);

      // Build table query data for each Inline attribute which is part of a filter
      // + compile query attribute
      foreach (QueryAttribute attr in compiledFilter.RequiredAttributes)
      {
        if (attr.Attr.Cardinality != Cardinality.Inline && attr.Attr.Cardinality != Cardinality.ManyToOne)
          continue;
        // Tables of Inline and MTO attributes, which are part of a filter, are joined with main table
        RequestedAttribute ra;
        RequestSimpleAttribute(attr, tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes,
            null, miaIdAttribute, out ra);
      }
      StringBuilder result = new StringBuilder("SELECT ");

      // Append MIA ID attribute only if no DISTINCT query is made
      result.Append(_selectProjectionFunction == null ?
          miaIdAttribute.GetDeclarationWithAlias(ns, out mediaItemIdAlias) :
          miaIdAttribute.GetDeclarationWithAlias(ns, _selectProjectionFunction, out mediaItemIdAlias));
      result.Append(", ");

      // Selected attributes
      result.Append(valueAttribute.GetDeclarationWithAlias(ns, out valueAlias));

      string whereStr = compiledFilter.CreateSqlFilterCondition(ns, requestedAttributes, out bindVars);

      result.Append(" FROM ");

      bool firstJoinTable = true;
      // Other joined tables
      foreach (TableJoin tableJoin in tableJoins)
      {
        if (firstJoinTable)
        {
          result.Append(tableJoin.JoinedTable.GetDeclarationWithAlias(ns));
          firstJoinTable = false;
        }
        else
          result.Append(tableJoin.GetJoinDeclaration(ns));
        result.Append(' ');
      }

      if (!string.IsNullOrEmpty(whereStr))
      {
        result.Append("WHERE ");
        result.Append(whereStr);
      }

      statementStr = result.ToString();
    }
示例#6
0
    protected void GenerateSqlStatement(bool groupByValues,
        IDictionary<MediaItemAspectMetadata, string> miamAliases,
        out string mediaItemIdOrGroupSizeAlias,
        out IDictionary<QueryAttribute, string> attributeAliases,
        out string statementStr, out IList<BindVar> bindVars)
    {
      Namespace ns = new Namespace();
      BindVarNamespace bvNamespace = new BindVarNamespace();

      // Contains a mapping of each queried (=selected or filtered) attribute to its request attribute instance
      // data (which holds its requested query table instance)
      IDictionary<QueryAttribute, RequestedAttribute> requestedAttributes = new Dictionary<QueryAttribute, RequestedAttribute>();
      attributeAliases = new Dictionary<QueryAttribute, string>();

      // Contains a list of qualified attribute names for all select attributes - needed for GROUP BY-expressions
      ICollection<string> qualifiedGroupByAliases = new List<string>();

      // Contains a list of compiled select attribute declarations. We need this in a separate list (in contrast to using
      // the selectAttributes list together with the compiledAttributes map) because it might be the case that
      // an attribute is requested twice. In that rare case, we need a new alias name for it.
      IList<string> selectAttributeDeclarations = new List<string>();

      // Dictionary containing as key the requested MIAM instance OR attribute specification of cardinality MTO,
      // mapped to the table query data to request its contents.
      IDictionary<object, TableQueryData> tableQueries = new Dictionary<object, TableQueryData>();

      // Contains the same tables as the tableQueries variable, but in order and enriched with table join data
      IList<TableJoin> tableJoins = new List<TableJoin>();

      // Contains all table query data for MIA type tables
      IDictionary<MediaItemAspectMetadata, TableQueryData> miaTypeTableQueries = new Dictionary<MediaItemAspectMetadata, TableQueryData>();

      // Albert, 2012-01-29: Optimized query, don't join with media items table, if we have necessary requested MIAs. In that case,
      // we can use one of their media item ids.
      //// First create the request table query data for the MIA main table and the request attribute for the MIA ID.
      //// We'll need the requested attribute as join attribute soon.
      //TableQueryData miaTableQuery = new TableQueryData(MediaLibrary_SubSchema.MEDIA_ITEMS_TABLE_NAME);
      //RequestedAttribute miaIdAttribute = new RequestedAttribute(miaTableQuery, MediaLibrary_SubSchema.MEDIA_ITEMS_ITEM_ID_COL_NAME);

      RequestedAttribute miaIdAttribute = null; // Lazy initialized below

      // Contains CompiledSortInformation instances for each sort information instance
      IList<CompiledSortInformation> compiledSortInformation = null;

      // Ensure that the tables for all necessary MIAs are requested first (INNER JOIN)
      foreach (MediaItemAspectMetadata miaType in _necessaryRequestedMIAs)
      {
        if (tableQueries.ContainsKey(miaType))
          // We only come here if miaType was already queried as necessary MIA, so optimize redundant entry
          continue;
        TableQueryData tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
        miaTypeTableQueries.Add(miaType, tqd);
        RequestedAttribute ra;
        // The first table join has invalid join attributes because miaIdAttribute is still null - but only the join table attribute is necessary
        // for the the first table - see below
        tableJoins.Add(new TableJoin("INNER JOIN", tqd,
            ra = new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
        if (miaIdAttribute == null)
          miaIdAttribute = ra;
      }

      if (miaIdAttribute == null)
      { // If we didn't request any necessary MIA types, we have to add an artificial table for the miaIdAttribute
        TableQueryData miaTableQuery = new TableQueryData(MediaLibrary_SubSchema.MEDIA_ITEMS_TABLE_NAME);
        tableJoins.Add(new TableJoin("INNER JOIN", miaTableQuery, null, null)); // First table join has invalid join attributes - not needed for first table
        miaIdAttribute = new RequestedAttribute(miaTableQuery, MediaLibrary_SubSchema.MEDIA_ITEMS_ITEM_ID_COL_NAME);
      }

      // Ensure that the tables for all optional MIAs are requested first (LEFT OUTER JOIN)
      // That is necessary to make empty optional MIA types available in the result
      foreach (MediaItemAspectMetadata miaType in _optionalRequestedMIAs)
      {
        if (tableQueries.ContainsKey(miaType))
          // We only come here if miaType was already queried as necessary or optional MIA, so optimize redundant entry
          continue;
        TableQueryData tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
        miaTypeTableQueries.Add(miaType, tqd);
        tableJoins.Add(new TableJoin("LEFT OUTER JOIN", tqd,
            new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
      }

      // Build table query data for each selected Inline and MTO attribute
      // + select query attribute
      // + add alias to selectAttributeDeclarations
      foreach (QueryAttribute attr in _selectAttributes)
      {
        RequestedAttribute ra;
        RequestSimpleAttribute(attr, tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes, miaTypeTableQueries,
            miaIdAttribute, out ra);
        string alias;
        selectAttributeDeclarations.Add(_selectProjectionFunction == null ?
            ra.GetDeclarationWithAlias(ns, out alias) :
            ra.GetDeclarationWithAlias(ns, _selectProjectionFunction, out alias));
        attributeAliases.Add(attr, alias);
        qualifiedGroupByAliases.Add(ra.GetAlias(ns));
      }

      CompiledFilter compiledFilter = new CompiledFilter(_miaManagement, _filter, ns, bvNamespace, miaIdAttribute.GetQualifiedName(ns), tableJoins);

      // Build table query data for each Inline attribute which is part of a filter
      // + compile query attribute
      foreach (QueryAttribute attr in compiledFilter.RequiredAttributes)
      {
        if (attr.Attr.Cardinality != Cardinality.Inline && attr.Attr.Cardinality != Cardinality.ManyToOne)
          continue;
        // Tables of Inline and MTO attributes, which are part of a filter, are joined with main table
        RequestedAttribute ra;
        RequestSimpleAttribute(attr, tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes,
            miaTypeTableQueries, miaIdAttribute, out ra);
      }
      // Build table query data for each sort attribute
      if (_sortInformation != null)
      {
        compiledSortInformation = new List<CompiledSortInformation>();
        foreach (SortInformation sortInformation in _sortInformation)
        {
          MediaItemAspectMetadata.AttributeSpecification attr = sortInformation.AttributeType;
          if (attr.Cardinality != Cardinality.Inline && attr.Cardinality != Cardinality.ManyToOne)
            // Sorting can only be done for Inline and MTO attributes
            continue;
          RequestedAttribute ra;
          RequestSimpleAttribute(new QueryAttribute(attr), tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes,
              miaTypeTableQueries, miaIdAttribute, out ra);
          compiledSortInformation.Add(new CompiledSortInformation(ra, sortInformation.Direction));
        }
      }
      StringBuilder result = new StringBuilder("SELECT ");

      string groupClause = StringUtils.Join(", ", qualifiedGroupByAliases.Select(alias => "V." + alias));
      if (groupByValues)
      {
        mediaItemIdOrGroupSizeAlias = "C";
        // Create an additional COUNT expression for the MEDIA_ITEMS.MEDIA_ITEM_ID in the GROUP BY-statement
        result.Append("COUNT(V.C) ");
        result.Append(mediaItemIdOrGroupSizeAlias);
        if (!string.IsNullOrWhiteSpace(groupClause))
        {
          result.Append(", ");
          result.Append(groupClause);
        }
        result.Append(" FROM (");
        result.Append("SELECT DISTINCT ");
        result.Append(miaIdAttribute.GetQualifiedName(ns));
        result.Append(" C");
      }
      else
      {
        // Append plain attribute MEDIA_ITEMS.MEDIA_ITEM_ID if no GROUP BY-statement is requested
        result.Append(miaIdAttribute.GetDeclarationWithAlias(ns, out mediaItemIdOrGroupSizeAlias));

        // System attributes: Necessary to evaluate if a requested MIA is present for the media item
        foreach (KeyValuePair<MediaItemAspectMetadata, TableQueryData> kvp in miaTypeTableQueries)
        {
          result.Append(", ");
          string miamColumn = kvp.Value.GetAlias(ns) + "." + MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME;
          result.Append(miamColumn);
          string miamAlias = ns.GetOrCreate(miamColumn, "A");
          result.Append(" ");
          result.Append(miamAlias);
          if (miamAlias != null)
            miamAliases.Add(kvp.Key, miamAlias);
        }
      }

      // Selected attributes
      foreach (string selectAttr in selectAttributeDeclarations)
      {
        result.Append(", ");
        result.Append(selectAttr);
      }

      string whereStr = compiledFilter.CreateSqlFilterCondition(ns, requestedAttributes, out bindVars);

      result.Append(" FROM ");

      bool firstJoinTable = true;
      // Other joined tables
      foreach (TableJoin tableJoin in tableJoins)
      {
        if (firstJoinTable)
        {
          result.Append(tableJoin.JoinedTable.GetDeclarationWithAlias(ns));
          firstJoinTable = false;
        }
        else
          result.Append(tableJoin.GetJoinDeclaration(ns));
        result.Append(' ');
      }

      if (!string.IsNullOrEmpty(whereStr))
      {
        result.Append("WHERE ");
        result.Append(whereStr);
      }
      if (groupByValues)
      {
        result.Append(") V");
        if (qualifiedGroupByAliases.Count > 0)
        {
          result.Append(" GROUP BY ");
          result.Append(groupClause);
        }
      }
      else
      {
        if (compiledSortInformation != null && compiledSortInformation.Count > 0)
        {
          IEnumerable<string> sortCriteria = compiledSortInformation.Select(csi => csi.GetSortDeclaration(ns));
          result.Append("ORDER BY ");
          result.Append(StringUtils.Join(", ", sortCriteria));
        }
      }

      statementStr = result.ToString();
    }
示例#7
0
        protected void GenerateSubSelectSqlStatement(BindVarNamespace bvNamespace,
                                                     out string statementStr, out IList <BindVar> bindVars)
        {
            Namespace ns = new Namespace();
            IDictionary <MediaItemAspectMetadata, string> miamAliases = new Dictionary <MediaItemAspectMetadata, string>();

            // Contains a mapping of each queried (=selected or filtered) attribute to its request attribute instance
            // data (which holds its requested query table instance)
            IDictionary <QueryAttribute, RequestedAttribute> requestedAttributes = new Dictionary <QueryAttribute, RequestedAttribute>();

            // Dictionary containing as key the requested MIAM instance OR attribute specification of cardinality MTO,
            // mapped to the table query data to request its contents.
            IDictionary <object, TableQueryData> tableQueries = new Dictionary <object, TableQueryData>();

            // Contains the same tables as the tableQueries variable, but in order and enriched with table join data
            IList <TableJoin> tableJoins = new List <TableJoin>();

            // Contains all table query data for MIA type tables
            IDictionary <MediaItemAspectMetadata, TableQueryData> miaTypeTableQueries = new Dictionary <MediaItemAspectMetadata, TableQueryData>();

            RequestedAttribute miaIdAttribute = null; // Lazy initialized below

            // Ensure that the tables for all necessary MIAs are requested first (INNER JOIN)
            foreach (MediaItemAspectMetadata miaType in _necessaryRequestedMIAs)
            {
                if (miaType.IsTransientAspect)
                {
                    continue;
                }
                if (tableQueries.ContainsKey(miaType))
                {
                    // We only come here if miaType was already queried as necessary MIA, so optimize redundant entry
                    continue;
                }

                TableQueryData tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
                miaTypeTableQueries.Add(miaType, tqd);
                RequestedAttribute ra;
                // The first table join has invalid join attributes because miaIdAttribute is still null - but only the join table attribute is necessary
                // for the the first table - see below
                tableJoins.Add(new TableJoin("INNER JOIN", tqd,
                                             ra = new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
                if (miaIdAttribute == null)
                {
                    miaIdAttribute = ra;
                }
            }

            if (miaIdAttribute == null)
            {                                                                           // If we didn't request any necessary MIA types, we have to add an artificial table for the miaIdAttribute
                TableQueryData miaTableQuery = new TableQueryData(MediaLibrary_SubSchema.MEDIA_ITEMS_TABLE_NAME);
                tableJoins.Add(new TableJoin("INNER JOIN", miaTableQuery, null, null)); // First table join has invalid join attributes - not needed for first table
                miaIdAttribute = new RequestedAttribute(miaTableQuery, MediaLibrary_SubSchema.MEDIA_ITEMS_ITEM_ID_COL_NAME);
            }

            // Ensure that the tables for all optional MIAs are requested first (LEFT OUTER JOIN)
            // That is necessary to make empty optional MIA types available in the result
            foreach (MediaItemAspectMetadata miaType in _optionalRequestedMIAs)
            {
                if (miaType.IsTransientAspect)
                {
                    continue;
                }
                if (tableQueries.ContainsKey(miaType))
                {
                    // We only come here if miaType was already queried as necessary or optional MIA, so optimize redundant entry
                    continue;
                }
                TableQueryData tqd = tableQueries[miaType] = TableQueryData.CreateTableQueryOfMIATable(_miaManagement, miaType);
                miaTypeTableQueries.Add(miaType, tqd);
                tableJoins.Add(new TableJoin("LEFT OUTER JOIN", tqd,
                                             new RequestedAttribute(tqd, MIA_Management.MIA_MEDIA_ITEM_ID_COL_NAME), miaIdAttribute));
            }

            CompiledFilter compiledFilter = CreateCompiledFilter(ns, bvNamespace, miaIdAttribute.GetQualifiedName(ns), tableJoins);

            // Build table query data for each Inline attribute which is part of a filter
            // + compile query attribute
            foreach (QueryAttribute attr in compiledFilter.RequiredAttributes)
            {
                if (attr.Attr.ParentMIAM.IsTransientAspect)
                {
                    continue;
                }
                if (attr.Attr.Cardinality != Cardinality.Inline && attr.Attr.Cardinality != Cardinality.ManyToOne)
                {
                    continue;
                }
                // Tables of Inline and MTO attributes, which are part of a filter, are joined with main table
                RequestedAttribute ra;
                RequestSimpleAttribute(attr, tableQueries, tableJoins, "LEFT OUTER JOIN", requestedAttributes,
                                       miaTypeTableQueries, miaIdAttribute, out ra);
            }

            StringBuilder result = new StringBuilder("SELECT ");

            result.Append(miaIdAttribute.GetQualifiedName(ns));

            string whereStr = compiledFilter.CreateSqlFilterCondition(ns, requestedAttributes, out bindVars);

            result.Append(" FROM ");

            bool firstJoinTable = true;

            // Other joined tables
            foreach (TableJoin tableJoin in tableJoins)
            {
                if (firstJoinTable)
                {
                    result.Append(tableJoin.JoinedTable.GetDeclarationWithAlias(ns));
                    firstJoinTable = false;
                }
                else
                {
                    result.Append(tableJoin.GetJoinDeclaration(ns));
                }
                result.Append(' ');
            }

            if (!string.IsNullOrEmpty(whereStr))
            {
                result.Append(" WHERE ");
                result.Append(whereStr);
            }

            statementStr = result.ToString();
        }