Yii Framework v1.1.10 类参考
CJoinElement
| 包 | system.db.ar |
|---|---|
| 继承 | class CJoinElement |
| 源自 | 1.0 |
| 版本 | $Id: CActiveFinder.php 3562 2012-02-13 01:27:06Z qiang.xue $ |
| 源码 | framework/db/ar/CActiveFinder.php |
CJoinElement表示一个在关联树中由CActiveFinder创建的子树节点。
公共属性
| 属性 | 类型 | 描述 | 定义在 |
|---|---|---|---|
| children | array | 子关联元素列表 | CJoinElement |
| id | integer | 树节点的唯一ID | CJoinElement |
| master | CActiveRelation | 主关系 | CJoinElement |
| model | CActiveRecord | 与树节点关联的模型 | CJoinElement |
| rawTableAlias | string | 此元素的引用表的别名 | CJoinElement |
| records | array | 此查询找到的活动记录列表，它们按主键值索引。 | CJoinElement |
| relation | CActiveRelation | 此树节点表示的关系 | CJoinElement |
| slave | CActiveRelation | 从关系 | CJoinElement |
| stats | array | 元素列表 | CJoinElement |
| tableAlias | string | 关联元素的表别名 | CJoinElement |
公共方法
| 方法 | 描述 | 定义在 |
|---|---|---|
| __construct() | 构造函数。 | CJoinElement |
| afterFind() | 调用所有记录的 CActiveRecord::afterFind . | CJoinElement |
| beforeFind() | 调用 CActiveRecord::beforeFind. | CJoinElement |
| buildQuery() | 建立关联查询并带有所有的依赖 HAS_ONE 和 BELONGS_TO 结点. | CJoinElement |
| count() | 返回关联语句查询出来的主记录的数目。 | CJoinElement |
| destroy() | 删除引用的子元素和查询，以避免循环引用。 | CJoinElement |
| find() | 根据查询实体执行循环轮询查找。 | CJoinElement |
| findWithBase() | 当基本记录可用的时候，执行预先加载。 | CJoinElement |
| getColumnPrefix() | 返回关联的字段前缀以用来消除歧义。 | CJoinElement |
| getColumnSelect() | 生成要查询的字段列表。 | CJoinElement |
| getJoinCondition() | 返回返回关联语句(这个结点与它的父结点连接) | CJoinElement |
| getPrimaryKeyRange() | 返回根据查询的主键值指定行的条件。 | CJoinElement |
| getPrimaryKeySelect() | 返回返回主键的选择 | CJoinElement |
| getTableNameWithAlias() | 返回返回表名和表别名（若有），这个可以无须转义直接在SQL查询中使用。 | CJoinElement |
| lazyFind() | 根据指定的基记录来执行延迟查找。 | CJoinElement |
| runQuery() | 执行关联查询并填充查询结果。 | CJoinElement |
属性详细
children
属性
public array $children;
子关联元素列表
id
属性
public integer $id;
树节点的唯一ID
master
属性
public CActiveRelation $master;
主关系
model
属性
public CActiveRecord $model;
与树节点关联的模型
rawTableAlias
属性
public string $rawTableAlias;
此元素的引用表的别名
records
属性
public array $records;
此查询找到的活动记录列表，它们按主键值索引。
relation
属性
public CActiveRelation $relation;
此树节点表示的关系
slave
属性
public CActiveRelation $slave;
从关系
stats
属性
public array $stats;
元素列表
tableAlias
属性
public string $tableAlias;
关联元素的表别名
方法详细
__construct()
方法
|
public void __construct(CActiveFinder $finder, mixed $relation, CJoinElement $parent=NULL, integer $id=0)
| ||
| $finder | CActiveFinder | 查询对象 |
| $relation | mixed | 关联到这个树节点的关系（如果第三个参数不为 null）， 或者是模型（如果第三个参数为 null）。 |
| $parent | CJoinElement | 父树节点 |
| $id | integer | 此树结点的ID，在所有树结点中是唯一的 |
源码： framework/db/ar/CActiveFinder.php#386 (显示)
public function __construct($finder,$relation,$parent=null,$id=0)
{
$this->_finder=$finder;
$this->id=$id;
if($parent!==null)
{
$this->relation=$relation;
$this->_parent=$parent;
$this->model=CActiveRecord::model($relation->className);
$this->_builder=$this->model->getCommandBuilder();
$this->tableAlias=$relation->alias===null?$relation->name:$relation->alias;
$this->rawTableAlias=$this->_builder->getSchema()->quoteTableName($this->tableAlias);
$this->_table=$this->model->getTableSchema();
}
else // root element, the first parameter is the model.
{
$this->model=$relation;
$this->_builder=$relation->getCommandBuilder();
$this->_table=$relation->getTableSchema();
$this->tableAlias=$this->model->getTableAlias();
$this->rawTableAlias=$this->_builder->getSchema()->quoteTableName($this->tableAlias);
}
// set up column aliases, such as t1_c2
$table=$this->_table;
if($this->model->getDbConnection()->getDriverName()==='oci') // Issue 482
$prefix='T'.$id.'_C';
else
$prefix='t'.$id.'_c';
foreach($table->getColumnNames() as $key=>$name)
{
$alias=$prefix.$key;
$this->_columnAliases[$name]=$alias;
if($table->primaryKey===$name)
$this->_pkAlias=$alias;
else if(is_array($table->primaryKey) && in_array($name,$table->primaryKey))
$this->_pkAlias[$name]=$alias;
}
}
构造函数。
afterFind()
方法
|
public void afterFind()
|
源码： framework/db/ar/CActiveFinder.php#781 (显示)
public function afterFind()
{
foreach($this->records as $record)
$record->afterFindInternal();
foreach($this->children as $child)
$child->afterFind();
$this->children = null;
}
调用所有记录的 CActiveRecord::afterFind .
beforeFind()
方法
|
public void beforeFind(boolean $isChild=true)
| ||
| $isChild | boolean | 是否作为一个子节点调用 |
源码： framework/db/ar/CActiveFinder.php#769 (显示)
public function beforeFind($isChild=true)
{
if($isChild)
$this->model->beforeFindInternal();
foreach($this->children as $child)
$child->beforeFind(true);
}
buildQuery()
方法
|
public void buildQuery(CJoinQuery $query)
| ||
| $query | CJoinQuery | 此查询被建立 |
源码： framework/db/ar/CActiveFinder.php#795 (显示)
public function buildQuery($query)
{
foreach($this->children as $child)
{
if($child->master!==null)
$child->_joined=true;
else if($child->relation instanceof CHasOneRelation || $child->relation instanceof CBelongsToRelation
|| $this->_finder->joinAll || $child->relation->together || (!$this->_finder->baseLimited && $child->relation->together===null))
{
$child->_joined=true;
$query->join($child);
$child->buildQuery($query);
}
}
}
建立关联查询并带有所有的依赖 HAS_ONE 和 BELONGS_TO 结点.
count()
方法
|
public string count(CDbCriteria $criteria=NULL)
| ||
| $criteria | CDbCriteria | 查询条件 |
| {return} | string | 返回主记录的数量。 注意: 类型为字符串保持最大精度。 |
源码： framework/db/ar/CActiveFinder.php#738 (显示)
public function count($criteria=null)
{
$query=new CJoinQuery($this,$criteria);
// ensure only one big join statement is used
$this->_finder->baseLimited=false;
$this->_finder->joinAll=true;
$this->buildQuery($query);
$select=is_array($criteria->select) ? implode(',',$criteria->select) : $criteria->select;
if($select!=='*' && !strncasecmp($select,'count',5))
$query->selects=array($select);
else if(is_string($this->_table->primaryKey))
{
$prefix=$this->getColumnPrefix();
$schema=$this->_builder->getSchema();
$column=$prefix.$schema->quoteColumnName($this->_table->primaryKey);
$query->selects=array("COUNT(DISTINCT $column)");
}
else
$query->selects=array("COUNT(*)");
$query->orders=$query->groups=$query->havings=array();
$query->limit=$query->offset=-1;
$command=$query->createCommand($this->_builder);
return $command->queryScalar();
}
返回关联语句查询出来的主记录的数目。
destroy()
方法
|
public void destroy()
|
源码： framework/db/ar/CActiveFinder.php#430 (显示)
public function destroy()
{
if(!empty($this->children))
{
foreach($this->children as $child)
$child->destroy();
}
unset($this->_finder, $this->_parent, $this->model, $this->relation, $this->master, $this->slave, $this->records, $this->children, $this->stats);
}
删除引用的子元素和查询，以避免循环引用。 这个方法是内部使用。
find()
方法
|
public void find(CDbCriteria $criteria=NULL)
| ||
| $criteria | CDbCriteria | the query criteria |
源码： framework/db/ar/CActiveFinder.php#444 (显示)
public function find($criteria=null)
{
if($this->_parent===null) // root element
{
$query=new CJoinQuery($this,$criteria);
$this->_finder->baseLimited=($criteria->offset>=0 || $criteria->limit>=0);
$this->buildQuery($query);
$this->_finder->baseLimited=false;
$this->runQuery($query);
}
else if(!$this->_joined && !empty($this->_parent->records)) // not joined before
{
$query=new CJoinQuery($this->_parent);
$this->_joined=true;
$query->join($this);
$this->buildQuery($query);
$this->_parent->runQuery($query);
}
foreach($this->children as $child) // find recursively
$child->find();
foreach($this->stats as $stat)
$stat->query();
}
根据查询实体执行循环轮询查找。
findWithBase()
方法
|
public void findWithBase(mixed $baseRecords)
| ||
| $baseRecords | mixed | 可用的基本记录。 |
源码： framework/db/ar/CActiveFinder.php#702 (显示)
public function findWithBase($baseRecords)
{
if(!is_array($baseRecords))
$baseRecords=array($baseRecords);
if(is_string($this->_table->primaryKey))
{
foreach($baseRecords as $baseRecord)
$this->records[$baseRecord->{$this->_table->primaryKey}]=$baseRecord;
}
else
{
foreach($baseRecords as $baseRecord)
{
$pk=array();
foreach($this->_table->primaryKey as $name)
$pk[$name]=$baseRecord->$name;
$this->records[serialize($pk)]=$baseRecord;
}
}
$query=new CJoinQuery($this);
$this->buildQuery($query);
if(count($query->joins)>1)
$this->runQuery($query);
foreach($this->children as $child)
$child->find();
foreach($this->stats as $stat)
$stat->query();
}
当基本记录可用的时候，执行预先加载。
getColumnPrefix()
方法
|
public string getColumnPrefix()
| ||
| {return} | string | 关联的字段前缀以用来消除歧义。 |
源码： framework/db/ar/CActiveFinder.php#1028 (显示)
public function getColumnPrefix()
{
if($this->tableAlias!==null)
return $this->rawTableAlias.'.';
else
return $this->_table->rawName.'.';
}
getColumnSelect()
方法
|
public string getColumnSelect(mixed $select='*')
| ||
| $select | mixed | 要查询的字段，默认值为 '*', 指示所有的字段。 |
| {return} | string | 返回字段选择 |
源码： framework/db/ar/CActiveFinder.php#919 (显示)
public function getColumnSelect($select='*')
{
$schema=$this->_builder->getSchema();
$prefix=$this->getColumnPrefix();
$columns=array();
if($select==='*')
{
foreach($this->_table->getColumnNames() as $name)
$columns[]=$prefix.$schema->quoteColumnName($name).' AS '.$schema->quoteColumnName($this->_columnAliases[$name]);
}
else
{
if(is_string($select))
$select=explode(',',$select);
$selected=array();
foreach($select as $name)
{
$name=trim($name);
$matches=array();
if(($pos=strrpos($name,'.'))!==false)
$key=substr($name,$pos+1);
else
$key=$name;
$key=trim($key,'\'"`');
if($key==='*')
{
foreach($this->_table->columns as $name=>$column)
{
$alias=$this->_columnAliases[$name];
if(!isset($selected[$alias]))
{
$columns[]=$prefix.$column->rawName.' AS '.$schema->quoteColumnName($alias);
$selected[$alias]=1;
}
}
continue;
}
if(isset($this->_columnAliases[$key])) // simple column names
{
$columns[]=$prefix.$schema->quoteColumnName($key).' AS '.$schema->quoteColumnName($this->_columnAliases[$key]);
$selected[$this->_columnAliases[$key]]=1;
}
else if(preg_match('/^(.*?)\s+AS\s+(\w+)$/im',$name,$matches)) // if the column is already aliased
{
$alias=$matches[2];
if(!isset($this->_columnAliases[$alias]) || $this->_columnAliases[$alias]!==$alias)
{
$this->_columnAliases[$alias]=$alias;
$columns[]=$name;
$selected[$alias]=1;
}
}
else
throw new CDbException(Yii::t('yii','Active record "{class}" is trying to select an invalid column "{column}". Note, the column must exist in the table or be an expression with alias.',
array('{class}'=>get_class($this->model), '{column}'=>$name)));
}
// add primary key selection if they are not selected
if(is_string($this->_pkAlias) && !isset($selected[$this->_pkAlias]))
$columns[]=$prefix.$schema->quoteColumnName($this->_table->primaryKey).' AS '.$schema->quoteColumnName($this->_pkAlias);
else if(is_array($this->_pkAlias))
{
foreach($this->_table->primaryKey as $name)
if(!isset($selected[$name]))
$columns[]=$prefix.$schema->quoteColumnName($name).' AS '.$schema->quoteColumnName($this->_pkAlias[$name]);
}
}
return implode(', ',$columns);
}
生成要查询的字段列表。 字段会正确处理别名，如果没有指定主键，那么会自动将主键加到查询语句。
getJoinCondition()
方法
|
public string getJoinCondition()
| ||
| {return} | string | 返回关联语句(这个结点与它的父结点连接) |
源码： framework/db/ar/CActiveFinder.php#1039 (显示)
public function getJoinCondition()
{
$parent=$this->_parent;
if($this->relation instanceof CManyManyRelation)
{
if(!preg_match('/^\s*(.*?)\((.*)\)\s*$/',$this->relation->foreignKey,$matches))
throw new CDbException(Yii::t('yii','The relation "{relation}" in active record class "{class}" is specified with an invalid foreign key. The format of the foreign key must be "joinTable(fk1,fk2,...)".',
array('{class}'=>get_class($parent->model),'{relation}'=>$this->relation->name)));
$schema=$this->_builder->getSchema();
if(($joinTable=$schema->getTable($matches[1]))===null)
throw new CDbException(Yii::t('yii','The relation "{relation}" in active record class "{class}" is not specified correctly: the join table "{joinTable}" given in the foreign key cannot be found in the database.',
array('{class}'=>get_class($parent->model), '{relation}'=>$this->relation->name, '{joinTable}'=>$matches[1])));
$fks=preg_split('/\s*,\s*/',$matches[2],-1,PREG_SPLIT_NO_EMPTY);
return $this->joinManyMany($joinTable,$fks,$parent);
}
else
{
$fks=is_array($this->relation->foreignKey) ? $this->relation->foreignKey : preg_split('/\s*,\s*/',$this->relation->foreignKey,-1,PREG_SPLIT_NO_EMPTY);
if($this->relation instanceof CBelongsToRelation)
{
$pke=$this;
$fke=$parent;
}
else if($this->slave===null)
{
$pke=$parent;
$fke=$this;
}
else
{
$pke=$this;
$fke=$this->slave;
}
return $this->joinOneMany($fke,$fks,$pke,$parent);
}
}
getPrimaryKeyRange()
方法
|
public string getPrimaryKeyRange()
| ||
| {return} | string | 根据查询的主键值指定行的条件。 |
源码： framework/db/ar/CActiveFinder.php#1012 (显示)
public function getPrimaryKeyRange()
{
if(empty($this->records))
return '';
$values=array_keys($this->records);
if(is_array($this->_table->primaryKey))
{
foreach($values as &$value)
$value=unserialize($value);
}
return $this->_builder->createInCondition($this->_table,$this->_table->primaryKey,$values,$this->getColumnPrefix());
}
getPrimaryKeySelect()
方法
|
public string getPrimaryKeySelect()
| ||
| {return} | string | 返回主键的选择 |
源码： framework/db/ar/CActiveFinder.php#994 (显示)
public function getPrimaryKeySelect()
{
$schema=$this->_builder->getSchema();
$prefix=$this->getColumnPrefix();
$columns=array();
if(is_string($this->_pkAlias))
$columns[]=$prefix.$schema->quoteColumnName($this->_table->primaryKey).' AS '.$schema->quoteColumnName($this->_pkAlias);
else if(is_array($this->_pkAlias))
{
foreach($this->_pkAlias as $name=>$alias)
$columns[]=$prefix.$schema->quoteColumnName($name).' AS '.$schema->quoteColumnName($alias);
}
return implode(', ',$columns);
}
getTableNameWithAlias()
方法
|
public string getTableNameWithAlias()
| ||
| {return} | string | 返回表名和表别名（若有），这个可以无须转义直接在SQL查询中使用。 |
源码： framework/db/ar/CActiveFinder.php#905 (显示)
public function getTableNameWithAlias()
{
if($this->tableAlias!==null)
return $this->_table->rawName . ' ' . $this->rawTableAlias;
else
return $this->_table->rawName;
}
lazyFind()
方法
|
public void lazyFind(CActiveRecord $baseRecord)
| ||
| $baseRecord | CActiveRecord | 要被获取活动记录的相关对象 |
源码： framework/db/ar/CActiveFinder.php#474 (显示)
public function lazyFind($baseRecord)
{
if(is_string($this->_table->primaryKey))
$this->records[$baseRecord->{$this->_table->primaryKey}]=$baseRecord;
else
{
$pk=array();
foreach($this->_table->primaryKey as $name)
$pk[$name]=$baseRecord->$name;
$this->records[serialize($pk)]=$baseRecord;
}
foreach($this->stats as $stat)
$stat->query();
switch(count($this->children))
{
case 0:
return;
break;
case 1:
$child=reset($this->children);
break;
default: // bridge(s) inside
$child=end($this->children);
break;
}
$query=new CJoinQuery($child);
$query->selects=array();
$query->selects[]=$child->getColumnSelect($child->relation->select);
$query->conditions=array();
$query->conditions[]=$child->relation->condition;
$query->conditions[]=$child->relation->on;
$query->groups[]=$child->relation->group;
$query->joins[]=$child->relation->join;
$query->havings[]=$child->relation->having;
$query->orders[]=$child->relation->order;
if(is_array($child->relation->params))
$query->params=$child->relation->params;
$query->elements[$child->id]=true;
if($child->relation instanceof CHasManyRelation)
{
$query->limit=$child->relation->limit;
$query->offset=$child->relation->offset;
}
$child->beforeFind();
$child->applyLazyCondition($query,$baseRecord);
$this->_joined=true;
$child->_joined=true;
$this->_finder->baseLimited=false;
$child->buildQuery($query);
$child->runQuery($query);
foreach($child->children as $c)
$c->find();
if(empty($child->records))
return;
if($child->relation instanceof CHasOneRelation || $child->relation instanceof CBelongsToRelation)
$baseRecord->addRelatedRecord($child->relation->name,reset($child->records),false);
else // has_many and many_many
{
foreach($child->records as $record)
{
if($child->relation->index!==null)
$index=$record->{$child->relation->index};
else
$index=true;
$baseRecord->addRelatedRecord($child->relation->name,$record,$index);
}
}
}
根据指定的基记录来执行延迟查找。
runQuery()
方法
|
public void runQuery(CJoinQuery $query)
| ||
| $query | CJoinQuery | 要被执行的查询。 |
源码： framework/db/ar/CActiveFinder.php#815 (显示)
public function runQuery($query)
{
$command=$query->createCommand($this->_builder);
foreach($command->queryAll() as $row)
$this->populateRecord($query,$row);
}
执行关联查询并填充查询结果。