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Count function using new query optimizer

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This commit is contained in:
Aaron
2009-02-20 15:19:41 -05:00
parent f786707c55
commit a4fc389f6b
3 changed files with 76 additions and 8 deletions
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68
db/queryoptimizer.cpp
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@@ -224,10 +224,14 @@ namespace mongo {
if ( !index_ )
return theDataFileMgr.findAll( fbs_.ns() );
else
return auto_ptr< Cursor >( new BtreeCursor( *const_cast< IndexDetails* >( index_ ), startKey_, endKey_, direction_ ) );
return auto_ptr< Cursor >( new BtreeCursor( *const_cast< IndexDetails* >( index_ ), startKey_, endKey_, direction_ >= 0 ? 1 : -1 ) );
//TODO This constructor should really take a const ref to the index details.
}
BSONObj QueryPlan::indexKey() const {
return index_->keyPattern();
}
QueryPlanSet::QueryPlanSet( const char *ns, const BSONObj &query, const BSONObj &order, const BSONElement *hint ) :
fbs_( ns, query ) {
NamespaceDetails *d = nsdetails( ns );
@@ -298,7 +302,6 @@ namespace mongo {
threads.create_thread( r );
}
threads.join_all();
cout << "really done" << endl;
for( int i = 0; i < plans_.nPlans(); ++i )
if ( ops[ i ]->done() )
return ops[ i ];
@@ -308,21 +311,74 @@ namespace mongo {
class CountOp : public QueryOp {
public:
CountOp( const BSONObj &spec ) : spec_( spec ), count_() {}
virtual void run( const QueryPlan &qp, QueryAborter &qa ) {
for( int i = 0; i < 100000; ++i )
BSONObj query = spec_.getObjectField("query");
set< string > fields;
spec_.getObjectField("fields").getFieldNames( fields );
auto_ptr<Cursor> c = qp.newCursor();
// TODO We could check if all fields in the key are in 'fields'
if ( qp.exactKeyMatch() && fields.empty() ) {
/* Here we only look at the btree keys to determine if a match, instead of looking
into the records, which would be much slower.
*/
BtreeCursor *bc = dynamic_cast<BtreeCursor *>(c.get());
if ( c->ok() && !query.woCompare( bc->currKeyNode().key, BSONObj(), false ) ) {
BSONObj firstMatch = bc->currKeyNode().key;
count_++;
while ( c->advance() ) {
qa.mayAbort();
if ( !firstMatch.woEqual( bc->currKeyNode().key ) )
break;
count_++;
}
}
return;
}
auto_ptr<JSMatcher> matcher(new JSMatcher(query, c->indexKeyPattern()));
while ( c->ok() ) {
qa.mayAbort();
cout << "done" << endl;
BSONObj js = c->current();
bool deep;
if ( !matcher->matches(js, &deep) ) {
}
else if ( !deep || !c->getsetdup(c->currLoc()) ) { // i.e., check for dups on deep items only
bool match = true;
for( set< string >::iterator i = fields.begin(); i != fields.end(); ++i ) {
if ( js.getFieldDotted( i->c_str() ).eoo() ) {
match = false;
break;
}
}
if ( match )
++count_;
}
c->advance();
}
}
virtual QueryOp *clone() const {
return new CountOp( *this );
}
int count() const { return 1; }
int count() const { return count_; }
private:
BSONObj spec_;
int count_;
};
int doCount( const char *ns, const BSONObj &cmd, string &err ) {
BSONObj query = cmd.getObjectField("query");
BSONObj fields = cmd.getObjectField("fields");
// count of all objects
if ( query.isEmpty() && fields.isEmpty() ) {
NamespaceDetails *d = nsdetails( ns );
massert( "ns missing", d );
return d->nrecords;
}
QueryPlanSet qps( ns, query, emptyObj );
auto_ptr< QueryOp > original( new CountOp () );
auto_ptr< QueryOp > original( new CountOp( cmd ) );
auto_ptr< QueryOp > o = qps.runOp( *original );
return dynamic_cast< CountOp* >( o.get() )->count();
}