timeseries_8h-source.html

FastDb是高效的内存数据库系统

00277         <a class="code" href="classdbCursor.html">dbCursor&lt; dbTimeSeriesBlock&lt;T&gt;</a> &gt; blocks;
00278         size_t nSelected = 0;
00279         <span class="keywordflow">if</span> (blocks.<a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a21">select</a>(selectBlock, dbCursorViewOnly, &amp;interval)) { 
00280             <span class="keywordflow">do</span> { 
00281                 <span class="keywordtype">int</span> n = blocks-&gt;used;
00282                 T <span class="keyword">const</span>* e =  blocks-&gt;elements.<a class="code" href="classdbCursor.html#dbCursora2">get</a>();
00283                 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; n &amp;&amp; e[i].time() &lt;= till; i++) { 
00284                     buf[nSelected++] = e[i];
00285                     <span class="keywordflow">if</span> (nSelected == bufSize) { 
00286                         <span class="keywordflow">return</span> nSelected;
00287                     }
00288                 }
00289             } <span class="keywordflow">while</span> (blocks.<a class="code" href="classdbCursor.html#dbCursora3">next</a>());
00290         }
00291         <span class="keywordflow">return</span> nSelected;
00292     }        
00293 
00294 
<a name="l00304"></a><a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora9">00304</a>     size_t <a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora9">getLastInterval</a>(oid_t oid, time_t from, T* buf, size_t bufSize) 
00305     {
00306         <span class="keywordflow">if</span> (bufSize == 0) { 
00307             <span class="keywordflow">return</span> 0;
00308         }
00309         Interval interval;
00310         interval.from = generateBlockId(oid, from == 0 ? 0 : from - maxBlockTimeInterval);
00311         interval.till = generateBlockId(oid, INFINITE_TIME);
00312         <a class="code" href="classdbCursor.html">dbCursor&lt; dbTimeSeriesBlock&lt;T&gt;</a> &gt; blocks;
00313 
00314         size_t nSelected = 0;
00315         blocks.<a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a21">select</a>(selectBlock, dbCursorViewOnly, &amp;interval);
00316         <span class="keywordflow">if</span> (blocks.<a class="code" href="classdbCursor.html#dbCursora6">last</a>()) { 
00317             <span class="keywordflow">do</span> { 
00318                 <span class="keywordtype">int</span> n = blocks-&gt;used;
00319                 T <span class="keyword">const</span>* e =  blocks-&gt;elements.<a class="code" href="classdbCursor.html#dbCursora2">get</a>();
00320                 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = n; --i &gt;= 0 &amp;&amp; e[i].time() &gt;= from;) { 
00321                     buf[nSelected++] = e[i];
00322                     <span class="keywordflow">if</span> (nSelected == bufSize) { 
00323                         <span class="keywordflow">return</span> nSelected;
00324                     }
00325                 }
00326             } <span class="keywordflow">while</span> (blocks.<a class="code" href="classdbCursor.html#dbCursora4">prev</a>());
00327         }
00328         <span class="keywordflow">return</span> nSelected;
00329     }        
00330 
00331 
00332 
<a name="l00339"></a><a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora10">00339</a>     <span class="keywordtype">bool</span> <a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora10">hasElement</a>(oid_t oid, time_t t) 
00340     { 
00341         T dummy;
00342         <span class="keywordflow">return</span> <a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora7">getElement</a>(oid, dummy, t);
00343     }        
00344 
<a name="l00356"></a><a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora11">00356</a>     <a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora11">dbTimeSeriesProcessor</a>(<a class="code" href="classdbDatabase.html">dbDatabase</a>&amp; database, <span class="keywordtype">int</span> minElementsInBlock=100, <span class="keywordtype">int</span> maxElementsInBlock=100, time_t maxBlockTimeInterval=0) :
00357         db(database) 
00358     {
00359         assert(minElementsInBlock &gt; 0 &amp;&amp; maxElementsInBlock &gt;= minElementsInBlock);
00360         <span class="keywordflow">if</span> (maxBlockTimeInterval == 0) { 
00361             maxBlockTimeInterval = 2*(maxElementsInBlock*24*60*60); <span class="comment">// doubled interval in seconds, one element per day</span>
00362         }        
00363         this-&gt;maxElementsInBlock = maxElementsInBlock;
00364         this-&gt;minElementsInBlock = minElementsInBlock;
00365         this-&gt;maxBlockTimeInterval = maxBlockTimeInterval;
00366 
00367         <span class="comment">// correct instance of interval will be specified in select</span>
00368         Interval* dummy = NULL;
00369         selectBlock = <span class="stringliteral">"blockId between"</span>,dummy-&gt;from,<span class="stringliteral">"and"</span>,dummy-&gt;till;
00370         selectBlockReverse = <span class="stringliteral">"blockId between"</span>,dummy-&gt;from,<span class="stringliteral">"and"</span>,dummy-&gt;till,<span class="stringliteral">"order by blockId desc"</span>;
00371     }
00372 
<a name="l00380"></a><a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora12">00380</a>     <span class="keywordtype">int</span> <a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora12">remove</a>(oid_t oid, time_t from, time_t till)
00381     {
00382         Interval interval;
00383         interval.from = generateBlockId(oid, from == 0 ? 0 : from - maxBlockTimeInterval);
00384         interval.till = generateBlockId(oid, till);
00385         <a class="code" href="classdbCursor.html">dbCursor&lt; dbTimeSeriesBlock&lt;T&gt;</a> &gt; blocks;
00386         size_t nRemoved = 0;
00387         <span class="keywordflow">if</span> (blocks.<a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a21">select</a>(selectBlock, dbCursorForUpdate, &amp;interval)) { 
00388             <span class="keywordflow">do</span> { 
00389                 <span class="keywordtype">int</span> n = blocks-&gt;used;
00390                 T <span class="keyword">const</span>* e =  blocks-&gt;elements.<a class="code" href="classdbCursor.html#dbCursora2">get</a>();
00391                 <span class="keywordtype">int</span> l = 0, r = n;
00392                 <span class="keywordflow">while</span> (l &lt; r)  {
00393                     <span class="keywordtype">int</span> i = (l+r) &gt;&gt; 1;
00394                     <span class="keywordflow">if</span> (from &gt; e[i].time()) { 
00395                         l = i+1;
00396                     } <span class="keywordflow">else</span> { 
00397                         r = i;
00398                     }
00399                 }
00400                 assert(l == r &amp;&amp; (l == n || e[l].time() &gt;= from)); 
00401                 <span class="keywordflow">while</span> (r &lt; n &amp;&amp; e[r].time() &lt;= till) {
00402                     r += 1;
00403                     nRemoved += 1;
00404                 }
00405                 <span class="keywordflow">if</span> (l == 0 &amp;&amp; r == n) { 
00406                     blocks.<a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a15">remove</a>();
00407                 } <span class="keywordflow">else</span> <span class="keywordflow">if</span> (l &lt; n &amp;&amp; l != r) { 
00408                     <span class="keywordflow">if</span> (l == 0) { 
00409                         blocks-&gt;blockId = generateBlockId(oid, e[r].time());
00410                     }
00411                     T* ue = blocks-&gt;elements.<a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a29">update</a>();
00412                     <span class="keywordflow">while</span> (r &lt; n) { 
00413                         ue[l++] = ue[r++];
00414                     }
00415                     blocks-&gt;used = l;
00416                     blocks.<a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a29">update</a>();
00417                 }
00418             } <span class="keywordflow">while</span> (blocks.<a class="code" href="classdbCursor.html#dbCursora12">nextAvailable</a>());
00419         }
00420         <span class="keywordflow">return</span> nRemoved;
00421     }        
00422     
00423     <span class="keyword">virtual</span>~<a class="code" href="classdbTimeSeriesProcessor.html">dbTimeSeriesProcessor</a>() {}
00424 
<a name="l00430"></a><a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora14">00430</a>     <span class="keywordtype">int</span> <a class="code" href="classdbTimeSeriesProcessor.html#dbTimeSeriesProcessora14">_openIteratorCursor</a>(<a class="code" href="classdbCursor.html">dbCursor</a>&lt; <a class="code" href="classdbTimeSeriesBlock.html">dbTimeSeriesBlock&lt;T&gt;</a> &gt;&amp; cursor, oid_t oid, time_t from, time_t till) 
00431     { 
00432         Interval interval;
00433         interval.from = generateBlockId(oid, from == 0 ? 0 : from - maxBlockTimeInterval);
00434         interval.till = generateBlockId(oid, till);
00435         <span class="keywordflow">return</span> cursor.select(selectBlock, dbCursorViewOnly, &amp;interval);
00436     }
00437 
00438    <span class="keyword">private</span>:
00439      db_int8 generateBlockId(oid_t oid, time_t date) 
00440      {
00441         <span class="keywordflow">return</span> cons_int8(oid, date);
00442      }
00443      
00444      
00445      <span class="keywordtype">void</span> addNewBlock(oid_t oid, T <span class="keyword">const</span>&amp; data)
00446      {
00447          <a class="code" href="classdbTimeSeriesBlock.html">dbTimeSeriesBlock&lt;T&gt;</a> block;
00448          block.<a class="code" href="classdbTimeSeriesBlock.html#dbTimeSeriesBlocko0">blockId</a> = generateBlockId(oid, data.time());
00449          block.<a class="code" href="classdbTimeSeriesBlock.html#dbTimeSeriesBlocko2">elements</a>.resize(minElementsInBlock);
00450          block.<a class="code" href="classdbTimeSeriesBlock.html#dbTimeSeriesBlocko1">used</a> = 1;
00451          block.<a class="code" href="classdbTimeSeriesBlock.html#dbTimeSeriesBlocko2">elements</a>.putat(0, data);
00452          insert(block);
00453      }
00454 
00455      <span class="keywordtype">void</span> insertInBlock(oid_t oid, <a class="code" href="classdbCursor.html">dbCursor</a>&lt; <a class="code" href="classdbTimeSeriesBlock.html">dbTimeSeriesBlock&lt;T&gt;</a> &gt;&amp; blocks, T <span class="keyword">const</span>&amp; data)
00456      {
00457          time_t t = data.time();
00458          <span class="keywordtype">int</span> i, n = blocks-&gt;used;
00459 
00460          T <span class="keyword">const</span>* e =  blocks-&gt;elements.get();
00461          <span class="keywordtype">int</span> l = 0, r = n;
00462          <span class="keywordflow">while</span> (l &lt; r)  {
00463              i = (l+r) &gt;&gt; 1;
00464              <span class="keywordflow">if</span> (t &gt; e[i].time()) { 
00465                  l = i+1;
00466              } <span class="keywordflow">else</span> { 
00467                  r = i;
00468              }
00469          }
00470          assert(l == r &amp;&amp; (l == n || e[l].time() &gt;= t));
00471          <span class="keywordflow">if</span> (r == 0) { 
00472              <span class="keywordflow">if</span> (e[n-1].time() - t &gt; maxBlockTimeInterval || n == maxElementsInBlock) { 
00473                  addNewBlock(oid, data);
00474                  <span class="keywordflow">return</span>;
00475              }
00476              blocks-&gt;blockId = generateBlockId(oid, t);
00477          } <span class="keywordflow">else</span> <span class="keywordflow">if</span> (r == n) {
00478              <span class="keywordflow">if</span> (t - e[0].time() &gt; maxBlockTimeInterval || n == maxElementsInBlock) { 
00479                  addNewBlock(oid, data);
00480                  <span class="keywordflow">return</span>;
00481              } 
00482          }
00483          <span class="keywordflow">if</span> ((size_t)n == blocks-&gt;elements.length()) { 
00484              <span class="keywordflow">if</span> (n == maxElementsInBlock) { 
00485                  T* u = blocks-&gt;elements.update();
00486                  addNewBlock(oid, u[n-1]);
00487                  <span class="keywordflow">for</span> (i = n; --i &gt; r; ) { 
00488                      u[i] = u[i-1];