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<title> TemplatedbTimeSeriesBlock&lt; T &gt; class Reference</title>
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<hr><h1>dbTimeSeriesBlock&lt; T &gt; Class Template Reference</h1><code>#include &lt;<a class="el" href="timeseries_8h-source.html">timeseries.h</a>&gt;</code>
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<hr><a name="_details"></a><h2>Detailed Description</h2>
<h3>template&lt;class T&gt;<br>
 class dbTimeSeriesBlock&lt; T &gt;</h3>

Time series block contaning array of elements. Grouping several elements in one block (record) reduce space overhead and increase processing speed.<br>
 <b>Attention!</b> This class is not serialized, so it is can be accessed only by one thread
<p>
 <em>You are defining your own time series class, for example:</em> <pre>
 class Stock {
   public:
     char const* name;
     TYPE_DESCRIPTOR((KEY(name, INDEXED)));
 };
 
 
 class Quote {
   public:
     int4        tickerDate;
     real4       bid;
     int4        bidSize;
     real4       ask;
     int4        askSize;
 
     time_t time() const { return tickerDate; } // this method should be defined 
 
     TYPE_DESCRIPTOR((FIELD(tickerDate), FIELD(bid), FIELD(bidSize), FIELD(ask), FIELD(askSize)));
 };
 typedef dbTimeSeriesBlock&lt;Quote&gt;  DailyBlock;
 REGISTER(DailyBlock);
 </pre>  <em>Now you can work with time series objects in the followin way:</em> <pre>
 <a class="el" href="classdbDatabase.html">dbDatabase</a> db;
 if (db.open("mydatabase.dbs")) {
     <a class="el" href="classdbTimeSeriesProcessor.html">dbTimeSeriesProcessor</a>&lt;Quote&gt; proc(db, MIN_ELEMENTS_IN_BLOCK,MAX_ELEMENTS_IN_BLOCK);
     Quote quote;
     // initialize quote
     Stock stock;
     stock.name = "AAD";
     oid_t stockId = insert(oid).getOid();
     proc.add(stockId, quote); // add new element in time series
 
     Quote quoteBuf[MAX_QUOTES];
     // select quotes for the specified interval
     int n = proc.getInterval(stockId, fromDate, tillDate, quoteBuf, MAX_QUOTES);
     for (int i = 0; i &lt; n; i++) {
         printf("bid=d ask=d<br>
", quoteBuf[i].bid, quoteBuf[i].ask);
     }
 } 
 </pre> 
<p>
<hr>The documentation for this class was generated from the following file:<ul>
<li><a class="el" href="timeseries_8h-source.html">timeseries.h</a></ul>
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