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Search found 3 results on 1 pages for 'ownage'.

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  • C++/Qt - Memory allocation question

    - by HardCoder1986
    Hello! I recently started investigating Qt for myself and have the following question: Suppose I have some QTreeWidget* widget. At some moment I want to add some items to it and this is done via the following call: QList<QTreeWidgetItem*> items; // Prepare the items QTreeWidgetItem* item1 = new QTreeWidgetItem(...); QTreeWidgetItem* item2 = new QTreeWidgetItem(...); items.append(item1); items.append(item2); widget->addTopLevelItems(items); So far it looks ok, but I don't actually understand who should control the objects' lifetime. I should explain this with an example: Let's say, another function calls widget->clear();. I don't know what happens beneath this call but I do think that memory allocated for item1 and item2 doesn't get disposed here, because their ownage wasn't actually transfered. And, bang, we have a memory leak. The question is the following - does Qt have something to offer for this kind of situation? I could use boost::shared_ptr or any other smart pointer and write something like shared_ptr<QTreeWidgetItem> ptr(new QTreeWidgetItem(...)); items.append(ptr.get()); but I don't know if the Qt itself would try to make explicit delete calls on my pointers (which would be disastrous since I state them as shared_ptr-managed). How would you solve this problem? Maybe everything is evident and I miss something really simple?

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  • How do I put data from multiple records into different columns?

    - by Bryan
    My two tables are titled analyzed and analyzedCopy3. I'm trying to put information from analyzedCopy3 into multiple columns in analyzed. Sample data from analyzedCopy3: readings_miu_id OriginalCol ColRSSIz 110001366 Frederick Road -108 110001366 Steel Street 110001366 Fifth Ave. 110001508 Steel Street -104 What I want to do is put the top 3 OriginalCol, ColRSSIz combinations into columns that I have in the table analyzed. In analyzed there is only one record for each unique readings_miu_id. Any ideas? Thanks in advance. Additional Info: By "top 3 OriginalCol, ColRSSIz combinations" I mean the first 3 combinations with the highest value in the ColRSSIz column. For any readings_miu_id there could be anywhere from 1 row of information to 6 rows of information. So at most I'm only wanting the top 3. If there is less than 3 rows for the readings_miu_id then the other columns need to be blank. Query that generates the table "analyzed": strSql4 = " SELECT readings_miu_id, Count(readings_miu_id) as NumberOfReads, First(PercentSuccessz) as PercentSuccess, First(Readingz)as Reading, First(MIUwindowz) as MIUwindow, First(SNz) as SN, First(Noisez) as Noise, First(RSSIz) as RSSI, First(ColRSSIz) as ColRSSI, First(MIURSSIz) as MIURSSI, First(Col1z) as Col1, First(Col1RSSIz) as Col1RSSI, First(Col2z) as Col2, First(Col2RSSIz) as Col2RSSI, First(Col3z) as Col3, First(Col3RSSIz) as Col3RSSI, First(Firmwarez) as Firmware, First(CFGDatez) as CFGDate, First(FreqCorrz) as FreqCorr, First(Activez) as Active, First(MeterTypez) as MeterType, First(OriginColz) as OriginCol, First(ColIDz) as ColID, First(Ownagez) as Ownage, First(SiteIDz) as SiteID, First(PremIDz) as PremID, First(prem_group1z) as prem_group1, First(prem_group2z) as prem_group2, First(ReadIDz) as ReadID, First(prem_addr1z) as prem_addr1 " & _ "INTO analyzed " & _ "FROM analyzedCopy2 " & _ "GROUP BY readings_miu_id, PremIDz; " DoCmd.SetWarnings False DoCmd.RunSQL strSql4 DoCmd.SetWarnings True

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