cursor_8h-source.html

FastDb是高效的内存数据库系统

00361     dbSelection        selection;
00362     <span class="keywordtype">bool</span>               allRecords;
00363     oid_t              firstId;
00364     oid_t              lastId;
00365     oid_t              currId;
00366     byte*              record;
00367     size_t             limit;
00368 
00369     int4*              bitmap; <span class="comment">// bitmap to avoid duplicates</span>
00370     size_t             bitmapSize;
00371     <span class="keywordtype">bool</span>               eliminateDuplicates;
00372     <span class="keywordtype">bool</span>               prefetch;
00373     <span class="keywordtype">bool</span>               removed; <span class="comment">// current record was removed</span>
00374     <span class="keywordtype">bool</span>               updateInProgress;
00375 
00376     <span class="keywordtype">void</span>*              paramBase;
00377     
00378     <span class="keywordtype">void</span> checkForDuplicates();
00379 
00380     <span class="keywordtype">bool</span> isMarked(oid_t oid) { 
00381         <span class="keywordflow">return</span> bitmap != NULL &amp;&amp; (bitmap[oid &gt;&gt; 5] &amp; (1 &lt;&lt; (oid &amp; 31))) != 0;
00382     }
00383 
00384     <span class="keywordtype">void</span> mark(oid_t oid) { 
00385         <span class="keywordflow">if</span> (bitmap != NULL) { 
00386             bitmap[oid &gt;&gt; 5] |= 1 &lt;&lt; (oid &amp; 31);
00387         }
00388     }    
00389 
00390     <span class="keywordtype">bool</span> add(oid_t oid) { 
00391         <span class="keywordflow">if</span> (selection.nRows &lt; limit) { 
00392             <span class="keywordflow">if</span> (eliminateDuplicates) { 
00393                 <span class="keywordflow">if</span> (bitmap[oid &gt;&gt; 5] &amp; (1 &lt;&lt; (oid &amp; 31))) { 
00394                     <span class="keywordflow">return</span> <span class="keyword">true</span>;
00395                 }
00396                 bitmap[oid &gt;&gt; 5] |= 1 &lt;&lt; (oid &amp; 31);
00397             } 
00398             selection.add(oid);
00399             <span class="keywordflow">return</span> selection.nRows &lt; limit;
00400         } 
00401         <span class="keywordflow">return</span> <span class="keyword">false</span>;
00402     }
00403 
00404     <span class="keywordtype">bool</span> gotoNext();
00405     <span class="keywordtype">bool</span> gotoPrev(); 
00406     <span class="keywordtype">bool</span> gotoFirst();
00407     <span class="keywordtype">bool</span> gotoLast();
00408     
00409     <span class="keywordtype">void</span> setCurrent(<a class="code" href="classdbAnyReference.html">dbAnyReference</a> <span class="keyword">const</span>&amp; ref);
00410 
00411     <span class="keywordtype">void</span> adjustReferences(size_t base, size_t size, <span class="keywordtype">long</span> shift) { 
00412         <span class="keywordflow">if</span> (currId != 0) { 
00413             table-&gt;columns-&gt;adjustReferences(record, base, size, shift);
00414         }
00415     }
00416 
00417     dbAnyCursor(<a class="code" href="classdbTableDescriptor.html">dbTableDescriptor</a>&amp; aTable, dbCursorType aType, byte* rec)
00418     : table(&amp;aTable),type(aType),defaultType(aType),
00419       allRecords(false),currId(0),record(rec)
00420     {
00421         db = aTable.<a class="code" href="classdbTableDescriptor.html#dbTableDescriptorp10">db</a>;
00422         limit = dbDefaultSelectionLimit;
00423         updateInProgress = <span class="keyword">false</span>;
00424         prefetch = <span class="keyword">true</span>;
00425         removed = <span class="keyword">false</span>;
00426         bitmap = NULL; 
00427         bitmapSize = 0;
00428         eliminateDuplicates = <span class="keyword">false</span>;
00429         paramBase = NULL;
00430     }
00431   <span class="keyword">public</span>:
00432     dbAnyCursor() 
00433     : table(NULL),type(dbCursorViewOnly),defaultType(dbCursorViewOnly),
00434           allRecords(false),currId(0),record(NULL)
00435     {
00436         limit = dbDefaultSelectionLimit;
00437         updateInProgress = <span class="keyword">false</span>;
00438         prefetch = <span class="keyword">false</span>;
00439         removed = <span class="keyword">false</span>;
00440         bitmap = NULL;
00441         bitmapSize = 0;
00442         eliminateDuplicates = <span class="keyword">false</span>;
00443         db = NULL;
00444         paramBase = NULL;
00445     }
00446     ~dbAnyCursor();
00447 };
00448 
00449 
00453 <span class="keyword">template</span>&lt;<span class="keyword">class</span> T&gt;
<a name="l00454"></a><a class="code" href="classdbCursor.html">00454</a> <span class="keyword">class </span><a class="code" href="classdbCursor.html">dbCursor</a> : <span class="keyword">public</span> dbAnyCursor { 
00455   <span class="keyword">protected</span>:
00456     T record;
00457     
00458   <span class="keyword">public</span>:
<a name="l00463"></a><a class="code" href="classdbCursor.html#dbCursora0">00463</a>     <a class="code" href="classdbCursor.html#dbCursora0">dbCursor</a>(dbCursorType type = dbCursorViewOnly) 
00464         : dbAnyCursor(T::dbDescriptor, type, (byte*)&amp;record) {}
00465 
<a name="l00472"></a><a class="code" href="classdbCursor.html#dbCursora1">00472</a>     <a class="code" href="classdbCursor.html#dbCursora0">dbCursor</a>(<a class="code" href="classdbDatabase.html">dbDatabase</a>* aDb, dbCursorType type = dbCursorViewOnly)
00473         : dbAnyCursor(T::dbDescriptor, type, (byte*)&amp;record)
00474     {
00475         db = aDb;
00476         <a class="code" href="classdbTableDescriptor.html">dbTableDescriptor</a>* theTable = db-&gt;<a class="code" href="classdbDatabase.html#dbSubSqla32">lookupTable</a>(table);
00477         <span class="keywordflow">if</span> (theTable != NULL) { 
00478             table = theTable;
00479         }
00480     }
00481 
<a name="l00486"></a><a class="code" href="classdbCursor.html#dbCursora2">00486</a>     T* <a class="code" href="classdbCursor.html#dbCursora2">get</a>() { 
00487         <span class="keywordflow">return</span> currId == 0 ? (T*)NULL : &amp;record; 
00488     }
00489     
<a name="l00494"></a><a class="code" href="classdbCursor.html#dbCursora3">00494</a>     T* <a class="code" href="classdbCursor.html#dbCursora3">next</a>() { 
00495         <span class="keywordflow">if</span> (gotoNext()) { 
00496             <a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a47">fetch</a>();
00497             <span class="keywordflow">return</span> &amp;record;
00498         }
00499         <span class="keywordflow">return</span> NULL;
00500     }
00501 
<a name="l00506"></a><a class="code" href="classdbCursor.html#dbCursora4">00506</a>     T* <a class="code" href="classdbCursor.html#dbCursora4">prev</a>() { 
00507         <span class="keywordflow">if</span> (gotoPrev()) { 
00508             <a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a47">fetch</a>();
00509             <span class="keywordflow">return</span> &amp;record;
00510         }
00511         <span class="keywordflow">return</span> NULL;
00512     }
00513 
<a name="l00518"></a><a class="code" href="classdbCursor.html#dbCursora5">00518</a>     T* <a class="code" href="classdbCursor.html#dbCursora5">first</a>() { 
00519         <span class="keywordflow">if</span> (gotoFirst()) {
00520             <a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a47">fetch</a>();
00521             <span class="keywordflow">return</span> &amp;record;
00522         }
00523         <span class="keywordflow">return</span> NULL;
00524     }
00525 
<a name="l00530"></a><a class="code" href="classdbCursor.html#dbCursora6">00530</a>     T* <a class="code" href="classdbCursor.html#dbCursora6">last</a>() { 
00531         <span class="keywordflow">if</span> (gotoLast()) {
00532             <a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a47">fetch</a>();
00533             <span class="keywordflow">return</span> &amp;record;
00534         }
00535         <span class="keywordflow">return</span> NULL;
00536     }    
00537     
<a name="l00543"></a><a class="code" href="classdbCursor.html#dbCursora7">00543</a>     <span class="keywordtype">int</span> <a class="code" href="classdbCursor.html#dbCursora7">seek</a>(<a class="code" href="classdbReference.html">dbReference&lt;T&gt;</a> <span class="keyword">const</span>&amp; ref) { 
00544         <span class="keywordflow">return</span> <a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a41">dbAnyCursor::seek</a>(ref.<a class="code" href="classdbAnyReference.html#dbReference_3_01Version_01_4a11">getOid</a>());
00545     }
00546 
<a name="l00551"></a><a class="code" href="classdbCursor.html#dbCursora8">00551</a>     T* <a class="code" href="classdbCursor.html#dbCursora8">operator -&gt;</a>() { 
00552         assert(currId != 0);
00553         <span class="keywordflow">return</span> &amp;record;
00554     }
00555 
<a name="l00561"></a><a class="code" href="classdbCursor.html#dbCursora9">00561</a>     T* <a class="code" href="classdbCursor.html#dbCursora9">at</a>(<a class="code" href="classdbReference.html">dbReference&lt;T&gt;</a> <span class="keyword">const</span>&amp; ref) { 
00562         setCurrent(ref);
00563         <span class="keywordflow">return</span> &amp;record;
00564     }
00565     
<a name="l00570"></a><a class="code" href="classdbCursor.html#dbCursora10">00570</a>     <span class="keywordtype">void</span> <a class="code" href="classdbCursor.html#dbCursora10">toArray</a>(<a class="code" href="classdbArray.html">dbArray</a>&lt; <a class="code" href="classdbReference.html">dbReference&lt;T&gt;</a> &gt;&amp; arr)<span class="keyword"> const </span>{ 
00571         arr.resize(selection.nRows);
00572         <a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a20">toArrayOfOid</a>((oid_t*)arr.base());
00573     }
00574 
<a name="l00579"></a><a class="code" href="classdbCursor.html#dbCursora11">00579</a>     <a class="code" href="classdbReference.html">dbReference&lt;T&gt;</a> <a class="code" href="classdbCursor.html#dbCursora11">currentId</a>()<span class="keyword"> const </span>{ 
00580         <span class="keywordflow">return</span> <a class="code" href="classdbReference.html">dbReference&lt;T&gt;</a>(currId);
00581     }
00582 
<a name="l00599"></a><a class="code" href="classdbCursor.html#dbCursora12">00599</a>     T* <a class="code" href="classdbCursor.html#dbCursora12">nextAvailable</a>() { 
00600         <span class="keywordflow">if</span> (!removed) { 
00601             <span class="keywordflow">return</span> <a class="code" href="classdbCursor.html#dbCursora3">next</a>(); 
00602         } <span class="keywordflow">else</span> { 
00603             removed = <span class="keyword">false</span>;
00604             <span class="keywordflow">return</span> <a class="code" href="classdbCursor.html#dbCursora2">get</a>();
00605         }
00606     }
00607 
<a name="l00612"></a><a class="code" href="classdbCursor.html#dbCursora13">00612</a>     <span class="keywordtype">bool</span> <a class="code" href="classdbCursor.html#dbCursora13">isInSelection</a>(<a class="code" href="classdbReference.html">dbReference&lt;T&gt;</a>&amp; ref)  <span class="keyword">const</span> {
00613         <span class="keywordflow">return</span> <a class="code" href="classdbAnyCursor.html#dbCursor_3_01Sequencer_01_4a46">dbAnyCursor::isInSelection</a>(ref.getOid());
00614     }
00615 };
00616 
00617 <span class="keyword">class </span>dbParallelQueryContext { 
00618   <span class="keyword">public</span>:
00619     <a class="code" href="classdbDatabase.html">dbDatabase</a>* <span class="keyword">const</span>      db;
00620     <a class="code" href="classdbCompiledQuery.html">dbCompiledQuery</a>* <span class="keyword">const</span> query;
00621     oid_t                  firstRow;
00622     <a class="code" href="classdbTable.html">dbTable</a>*               table;
00623     dbAnyCursor*           cursor;
00624     dbSelection            selection[dbMaxParallelSearchThreads];
00625 
00626     <span class="keywordtype">void</span> search(<span class="keywordtype">int</span> i); 
00627 
00628     dbParallelQueryContext(<a class="code" href="classdbDatabase.html">dbDatabase</a>* aDb, <a class="code" href="classdbTable.html">dbTable</a>* aTable, 
00629                            <a class="code" href="classdbCompiledQuery.html">dbCompiledQuery</a>* aQuery, dbAnyCursor* aCursor)
00630       : db(aDb), query(aQuery), firstRow(aTable-&gt;firstRow), table(aTable), cursor(aCursor) {}
00631 };
00632 
00633 
00634 <span class="keyword">extern</span> <span class="keywordtype">char</span>* strupper(<span class="keywordtype">char</span>* s);
00635 
00636 <span class="keyword">extern</span> <span class="keywordtype">char</span>* strlower(<span class="keywordtype">char</span>* s);
00637 
00638 <span class="preprocessor">#endif</span>
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