PHP DBObjectSearch::FromEmptySet方法代码示例

 protected function GetSQLQuery($aOrderBy, $aArgs, $aAttToLoad, $aExtendedDataSpec, $iLimitCount, $iLimitStart, $bGetCount, $aGroupByExpr = null)
 {
     // Hide objects that are not visible to the current user
     //
     $oSearch = $this;
     if (!$this->IsAllDataAllowed() && !$this->IsDataFiltered()) {
         $oVisibleObjects = UserRights::GetSelectFilter($this->GetClass(), $this->GetModifierProperties('UserRightsGetSelectFilter'));
         if ($oVisibleObjects === false) {
             // Make sure this is a valid search object, saying NO for all
             $oVisibleObjects = DBObjectSearch::FromEmptySet($this->GetClass());
         }
         if (is_object($oVisibleObjects)) {
             $oSearch = $this->Intersect($oVisibleObjects);
             $oSearch->SetDataFiltered();
         } else {
             // should be true at this point, meaning that no additional filtering
             // is required
         }
     }
     // Compute query modifiers properties (can be set in the search itself, by the context, etc.)
     //
     $aModifierProperties = MetaModel::MakeModifierProperties($oSearch);
     // Create a unique cache id
     //
     if (self::$m_bQueryCacheEnabled || self::$m_bTraceQueries) {
         // Need to identify the query
         $sOqlQuery = $oSearch->ToOql();
         if (count($aModifierProperties)) {
             array_multisort($aModifierProperties);
             $sModifierProperties = json_encode($aModifierProperties);
         } else {
             $sModifierProperties = '';
         }
         $sRawId = $sOqlQuery . $sModifierProperties;
         if (!is_null($aAttToLoad)) {
             $sRawId .= json_encode($aAttToLoad);
         }
         if (!is_null($aGroupByExpr)) {
             foreach ($aGroupByExpr as $sAlias => $oExpr) {
                 $sRawId .= 'g:' . $sAlias . '!' . $oExpr->Render();
             }
         }
         $sRawId .= $bGetCount;
         $sOqlId = md5($sRawId);
     } else {
         $sOqlQuery = "SELECTING... " . $oSearch->GetClass();
         $sOqlId = "query id ? n/a";
     }
     // Query caching
     //
     if (self::$m_bQueryCacheEnabled) {
         // Warning: using directly the query string as the key to the hash array can FAIL if the string
         // is long and the differences are only near the end... so it's safer (but not bullet proof?)
         // to use a hash (like md5) of the string as the key !
         //
         // Example of two queries that were found as similar by the hash array:
         // SELECT SLT JOIN lnkSLTToSLA AS L1 ON L1.slt_id=SLT.id JOIN SLA ON L1.sla_id = SLA.id JOIN lnkContractToSLA AS L2 ON L2.sla_id = SLA.id JOIN CustomerContract ON L2.contract_id = CustomerContract.id WHERE SLT.ticket_priority = 1 AND SLA.service_id = 3 AND SLT.metric = 'TTO' AND CustomerContract.customer_id = 2
         // and
         // SELECT SLT JOIN lnkSLTToSLA AS L1 ON L1.slt_id=SLT.id JOIN SLA ON L1.sla_id = SLA.id JOIN lnkContractToSLA AS L2 ON L2.sla_id = SLA.id JOIN CustomerContract ON L2.contract_id = CustomerContract.id WHERE SLT.ticket_priority = 1 AND SLA.service_id = 3 AND SLT.metric = 'TTR' AND CustomerContract.customer_id = 2
         // the only difference is R instead or O at position 285 (TTR instead of TTO)...
         //
         if (array_key_exists($sOqlId, self::$m_aQueryStructCache)) {
             // hit!
             $oSQLQuery = unserialize(serialize(self::$m_aQueryStructCache[$sOqlId]));
             // Note: cloning is not enough because the subtree is made of objects
         } elseif (self::$m_bUseAPCCache) {
             // Note: For versions of APC older than 3.0.17, fetch() accepts only one parameter
             //
             $sOqlAPCCacheId = 'itop-' . MetaModel::GetEnvironmentId() . '-query-cache-' . $sOqlId;
             $oKPI = new ExecutionKPI();
             $result = apc_fetch($sOqlAPCCacheId);
             $oKPI->ComputeStats('Query APC (fetch)', $sOqlQuery);
             if (is_object($result)) {
                 $oSQLQuery = $result;
                 self::$m_aQueryStructCache[$sOqlId] = $oSQLQuery;
             }
         }
     }
     if (!isset($oSQLQuery)) {
         $oKPI = new ExecutionKPI();
         $oSQLQuery = $oSearch->MakeSQLQuery($aAttToLoad, $bGetCount, $aModifierProperties, $aGroupByExpr);
         $oSQLQuery->SetSourceOQL($sOqlQuery);
         $oKPI->ComputeStats('MakeSQLQuery', $sOqlQuery);
         if (self::$m_bQueryCacheEnabled) {
             if (self::$m_bUseAPCCache) {
                 $oKPI = new ExecutionKPI();
                 apc_store($sOqlAPCCacheId, $oSQLQuery, self::$m_iQueryCacheTTL);
                 $oKPI->ComputeStats('Query APC (store)', $sOqlQuery);
             }
             self::$m_aQueryStructCache[$sOqlId] = $oSQLQuery->DeepClone();
         }
     }
     // Join to an additional table, if required...
     //
     if ($aExtendedDataSpec != null) {
         $sTableAlias = '_extended_data_';
         $aExtendedFields = array();
         foreach ($aExtendedDataSpec['fields'] as $sColumn) {
             $sColRef = $oSearch->GetClassAlias() . '_extdata_' . $sColumn;
             $aExtendedFields[$sColRef] = new FieldExpressionResolved($sColumn, $sTableAlias);
//.........这里部分代码省略.........