silverstripe-framework/model/DataQuery.php
2012-06-14 17:20:35 -07:00

750 lines
22 KiB
PHP

<?php
/**
* An object representing a query of data from the DataObject's supporting database.
* Acts as a wrapper over {@link SQLQuery} and performs all of the query generation.
* Used extensively by {@link DataList}.
*
* @subpackage model
* @package sapphire
*/
class DataQuery {
/**
* @var String
*/
protected $dataClass;
/**
* @var SQLQuery
*/
protected $query;
/**
* @var array
*/
protected $collidingFields = array();
private $queriedColumns = null;
/**
* @var Boolean
*/
private $queryFinalised = false;
// TODO: replace subclass_access with this
protected $querySubclasses = true;
// TODO: replace restrictclasses with this
protected $filterByClassName = true;
/**
* Create a new DataQuery.
*
* @param String The name of the DataObject class that you wish to query
*/
function __construct($dataClass) {
$this->dataClass = $dataClass;
$this->initialiseQuery();
}
/**
* Clone this object
*/
function __clone() {
$this->query = clone $this->query;
}
/**
* Return the {@link DataObject} class that is being queried.
*/
function dataClass() {
return $this->dataClass;
}
/**
* Return the {@link SQLQuery} object that represents the current query; note that it will
* be a clone of the object.
*/
function query() {
return $this->getFinalisedQuery();
}
/**
* Remove a filter from the query
*/
function removeFilterOn($fieldExpression) {
$matched = false;
$where = $this->query->getWhere();
foreach($where as $i => $clause) {
if(strpos($clause, $fieldExpression) !== false) {
unset($where[$i]);
$matched = true;
}
}
// set the entire where clause back, but clear the original one first
if($matched) {
$this->query->setWhere($where);
} else {
throw new InvalidArgumentException("Couldn't find $fieldExpression in the query filter.");
}
return $this;
}
/**
* Set up the simplest initial query
*/
function initialiseQuery() {
// Get the tables to join to.
// Don't get any subclass tables - let lazy loading do that.
$tableClasses = ClassInfo::ancestry($this->dataClass, true);
// Error checking
if(!$tableClasses) {
if(!SS_ClassLoader::instance()->hasManifest()) {
user_error("DataObjects have been requested before the manifest is loaded. Please ensure you are not querying the database in _config.php.", E_USER_ERROR);
} else {
user_error("DataObject::buildSQL: Can't find data classes (classes linked to tables) for $this->dataClass. Please ensure you run dev/build after creating a new DataObject.", E_USER_ERROR);
}
}
$baseClass = array_shift($tableClasses);
// Build our intial query
$this->query = new SQLQuery(array());
$this->query->setDistinct(true);
if($sort = singleton($this->dataClass)->stat('default_sort')) {
$this->sort($sort);
}
$this->query->setFrom("\"$baseClass\"");
$obj = Injector::inst()->get($baseClass);
$obj->extend('augmentDataQueryCreation', $this->query, $this);
}
function setQueriedColumns($queriedColumns) {
$this->queriedColumns = $queriedColumns;
}
/**
* Ensure that the query is ready to execute.
*/
function getFinalisedQuery($queriedColumns = null) {
if(!$queriedColumns) $queriedColumns = $this->queriedColumns;
if($queriedColumns) {
$queriedColumns = array_merge($queriedColumns, array('Created', 'LastEdited', 'ClassName'));
}
$query = clone $this->query;
// Generate the list of tables to iterate over and the list of columns required by any existing where clauses.
// This second step is skipped if we're fetching the whole dataobject as any required columns will get selected
// regardless.
if($queriedColumns) {
$tableClasses = ClassInfo::dataClassesFor($this->dataClass);
foreach ($query->getWhere() as $where) {
// Check for just the column, in the form '"Column" = ?' and the form '"Table"."Column"' = ?
if (preg_match('/^"([^"]+)"/', $where, $matches) ||
preg_match('/^"([^"]+)"\."[^"]+"/', $where, $matches)) {
if (!in_array($matches[1], $queriedColumns)) $queriedColumns[] = $matches[1];
}
}
}
else $tableClasses = ClassInfo::ancestry($this->dataClass, true);
$tableNames = array_keys($tableClasses);
$baseClass = $tableNames[0];
// Iterate over the tables and check what we need to select from them. If any selects are made (or the table is
// required for a select)
foreach($tableClasses as $tableClass) {
$joinTable = false;
// If queriedColumns is set, then check if any of the fields are in this table.
if ($queriedColumns) {
$tableFields = DataObject::database_fields($tableClass);
$selectColumns = array();
// Look through columns specifically requested in query (or where clause)
foreach ($queriedColumns as $queriedColumn) {
if (array_key_exists($queriedColumn, $tableFields)) {
$selectColumns[] = $queriedColumn;
}
}
$this->selectColumnsFromTable($query, $tableClass, $selectColumns);
if ($selectColumns && $tableClass != $baseClass) {
$joinTable = true;
}
} else {
$this->selectColumnsFromTable($query, $tableClass);
if ($tableClass != $baseClass) $joinTable = true;
}
if ($joinTable) {
$query->addLeftJoin($tableClass, "\"$tableClass\".\"ID\" = \"$baseClass\".\"ID\"") ;
}
}
// Resolve colliding fields
if($this->collidingFields) {
foreach($this->collidingFields as $k => $collisions) {
$caseClauses = array();
foreach($collisions as $collision) {
if(preg_match('/^"([^"]+)"/', $collision, $matches)) {
$collisionBase = $matches[1];
$collisionClasses = ClassInfo::subclassesFor($collisionBase);
$collisionClasses = array_map(array(DB::getConn(), 'prepStringForDB'), $collisionClasses);
$caseClauses[] = "WHEN \"$baseClass\".\"ClassName\" IN ("
. implode(", ", $collisionClasses) . ") THEN $collision";
} else {
user_error("Bad collision item '$collision'", E_USER_WARNING);
}
}
$query->selectField("CASE " . implode( " ", $caseClauses) . " ELSE NULL END", $k);
}
}
if($this->filterByClassName) {
// If querying the base class, don't bother filtering on class name
if($this->dataClass != $baseClass) {
// Get the ClassName values to filter to
$classNames = ClassInfo::subclassesFor($this->dataClass);
if(!$classNames) user_error("DataList::create() Can't find data sub-classes for '$callerClass'");
$classNames = array_map(array(DB::getConn(), 'prepStringForDB'), $classNames);
$query->addWhere("\"$baseClass\".\"ClassName\" IN (" . implode(",", $classNames) . ")");
}
}
$query->selectField("\"$baseClass\".\"ID\"", "ID");
$query->selectField("CASE WHEN \"$baseClass\".\"ClassName\" IS NOT NULL THEN \"$baseClass\".\"ClassName\" ELSE '$baseClass' END", "RecordClassName");
// TODO: Versioned, Translatable, SiteTreeSubsites, etc, could probably be better implemented as subclasses of DataQuery
$obj = Injector::inst()->get(ClassInfo::baseDataClass($this->dataClass));
$obj->extend('augmentSQL', $query, $this);
$this->ensureSelectContainsOrderbyColumns($query);
return $query;
}
/**
* Ensure that if a query has an order by clause, those columns are present in the select.
*
* @param SQLQuery $query
* @return null
*/
protected function ensureSelectContainsOrderbyColumns($query, $originalSelect = array()) {
$tableClasses = ClassInfo::dataClassesFor($this->dataClass);
$baseClass = array_shift($tableClasses);
if($orderby = $query->getOrderBy()) {
foreach($orderby as $k => $dir) {
// don't touch functions in the ORDER BY or function calls
// selected as fields
if(strpos($k, '(') !== false) continue;
$col = str_replace('"', '', trim($k));
$parts = explode('.', $col);
// Pull through SortColumn references from the originalSelect variables
if(preg_match('/_SortColumn/', $col)) {
if(isset($originalSelect[$col])) $query->selectField($originalSelect[$col], $col);
continue;
}
if(count($parts) == 1) {
$databaseFields = DataObject::database_fields($baseClass);
// database_fields() doesn't return ID, so we need to
// manually add it here
$databaseFields['ID'] = true;
if(isset($databaseFields[$parts[0]])) {
$qualCol = "\"$baseClass\".\"{$parts[0]}\"";
// remove original sort
unset($orderby[$k]);
// add new columns sort
$orderby[$qualCol] = $dir;
} else {
$qualCol = "\"$parts[0]\"";
}
// To-do: Remove this if block once SQLQuery::$select has been refactored to store getSelect()
// format internally; then this check can be part of selectField()
$selects = $query->getSelect();
if(!isset($selects[$col]) && !in_array($qualCol, $selects)) {
$query->selectField($qualCol);
}
} else {
$qualCol = '"' . implode('"."', $parts) . '"';
// To-do: Remove this if block once SQLQuery::$select has been refactored to store getSelect()
// format internally; then this check can be part of selectField()
if(!in_array($qualCol, $query->getSelect())) {
$query->selectField($qualCol);
}
}
}
$query->setOrderBy($orderby);
}
}
/**
* Execute the query and return the result as {@link Query} object.
*/
function execute() {
return $this->getFinalisedQuery()->execute();
}
/**
* Return this query's SQL
*/
function sql() {
return $this->getFinalisedQuery()->sql();
}
/**
* Return the number of records in this query.
* Note that this will issue a separate SELECT COUNT() query.
*/
function count() {
$baseClass = ClassInfo::baseDataClass($this->dataClass);
return $this->getFinalisedQuery()->count("DISTINCT \"$baseClass\".\"ID\"");
}
/**
* Return the maximum value of the given field in this DataList
*
* @param String $field Unquoted database column name (will be escaped automatically)
*/
function max($field) {
return $this->aggregate(sprintf('MAX("%s")', Convert::raw2sql($field)));
}
/**
* Return the minimum value of the given field in this DataList
*
* @param String $field Unquoted database column name (will be escaped automatically)
*/
function min($field) {
return $this->aggregate(sprintf('MIN("%s")', Convert::raw2sql($field)));
}
/**
* Return the average value of the given field in this DataList
*
* @param String $field Unquoted database column name (will be escaped automatically)
*/
function avg($field) {
return $this->aggregate(sprintf('AVG("%s")', Convert::raw2sql($field)));
}
/**
* Return the sum of the values of the given field in this DataList
*
* @param String $field Unquoted database column name (will be escaped automatically)
*/
function sum($field) {
return $this->aggregate(sprintf('SUM("%s")', Convert::raw2sql($field)));
}
/**
* Runs a raw aggregate expression. Please handle escaping yourself
*/
function aggregate($expression) {
return $this->getFinalisedQuery()->aggregate($expression)->execute()->value();
}
/**
* Return the first row that would be returned by this full DataQuery
* Note that this will issue a separate SELECT ... LIMIT 1 query.
*/
function firstRow() {
return $this->getFinalisedQuery()->firstRow();
}
/**
* Return the last row that would be returned by this full DataQuery
* Note that this will issue a separate SELECT ... LIMIT query.
*/
function lastRow() {
return $this->getFinalisedQuery()->lastRow();
}
/**
* Update the SELECT clause of the query with the columns from the given table
*/
protected function selectColumnsFromTable(SQLQuery &$query, $tableClass, $columns = null) {
// Add SQL for multi-value fields
$databaseFields = DataObject::database_fields($tableClass);
$compositeFields = DataObject::composite_fields($tableClass, false);
if($databaseFields) foreach($databaseFields as $k => $v) {
if((is_null($columns) || in_array($k, $columns)) && !isset($compositeFields[$k])) {
// Update $collidingFields if necessary
if($expressionForField = $query->expressionForField($k)) {
if(!isset($this->collidingFields[$k])) $this->collidingFields[$k] = array($expressionForField);
$this->collidingFields[$k][] = "\"$tableClass\".\"$k\"";
} else {
$query->selectField("\"$tableClass\".\"$k\"", $k);
}
}
}
if($compositeFields) foreach($compositeFields as $k => $v) {
if((is_null($columns) || in_array($k, $columns)) && $v) {
$dbO = Object::create_from_string($v, $k);
$dbO->addToQuery($query);
}
}
}
/**
* Set the HAVING clause of this query
*
* @param String $having Escaped SQL statement
*/
function having($having) {
if($having) {
$clone = $this;
$clone->query->addHaving($having);
return $clone;
} else {
return $this;
}
}
/**
* Set the WHERE clause of this query.
* There are two different ways of doing this:
*
* <code>
* // the entire predicate as a single string
* $query->where("Column = 'Value'");
*
* // multiple predicates as an array
* $query->where(array("Column = 'Value'", "Column != 'Value'"));
* </code>
*
* @param string|array $where Predicate(s) to set, as escaped SQL statements.
*/
function where($filter) {
if($filter) {
$clone = $this;
$clone->query->addWhere($filter);
return $clone;
} else {
return $this;
}
}
/**
* Set a WHERE with OR.
*
* @example $dataQuery->whereAny(array("Monkey = 'Chimp'", "Color = 'Brown'"));
* @see where()
*
* @param array $filter Escaped SQL statement.
* @return DataQuery
*/
function whereAny($filter) {
if($filter) {
$clone = $this;
$clone->query->whereAny($filter);
return $clone;
} else {
return $this;
}
}
/**
* Set the ORDER BY clause of this query
*
* @see SQLQuery::orderby()
*
* @param String $sort Column to sort on (escaped SQL statement)
* @param String $direction Direction ("ASC" or "DESC", escaped SQL statement)
* @param Boolean $clear Clear existing values
* @return DataQuery
*/
function sort($sort = null, $direction = null, $clear = true) {
$clone = $this;
if($clear) {
$clone->query->setOrderBy($sort, $direction);
} else {
$clone->query->addOrderBy($sort, $direction);
}
return $clone;
}
/**
* Reverse order by clause
*
* @return DataQuery
*/
function reverseSort() {
$clone = $this;
$clone->query->reverseOrderBy();
return $clone;
}
/**
* Set the limit of this query.
*
* @param int $limit
* @param int $offset
*/
function limit($limit, $offset = 0) {
$clone = $this;
$clone->query->setLimit($limit, $offset);
return $clone;
}
/**
* Add a join clause to this query
* @deprecated 3.0 Use innerJoin() or leftJoin() instead.
*/
function join($join) {
Deprecation::notice('3.0', 'Use innerJoin() or leftJoin() instead.');
if($join) {
$clone = $this;
$clone->query->addFrom($join);
// TODO: This needs to be resolved for all databases
if(DB::getConn() instanceof MySQLDatabase) {
$from = $clone->query->getFrom();
$clone->query->setGroupBy(reset($from) . ".\"ID\"");
}
return $clone;
} else {
return $this;
}
}
/**
* Add an INNER JOIN clause to this query.
*
* @param String $table The unquoted table name to join to.
* @param String $onClause The filter for the join (escaped SQL statement)
* @param String $alias An optional alias name (unquoted)
*/
public function innerJoin($table, $onClause, $alias = null) {
if($table) {
$clone = $this;
$clone->query->addInnerJoin($table, $onClause, $alias);
return $clone;
} else {
return $this;
}
}
/**
* Add a LEFT JOIN clause to this query.
*
* @param String $table The unquoted table to join to.
* @param String $onClause The filter for the join (escaped SQL statement).
* @param String $alias An optional alias name (unquoted)
*/
public function leftJoin($table, $onClause, $alias = null) {
if($table) {
$clone = $this;
$clone->query->addLeftJoin($table, $onClause, $alias);
return $clone;
} else {
return $this;
}
}
/**
* Traverse the relationship fields, and add the table
* mappings to the query object state. This has to be called
* in any overloaded {@link SearchFilter->apply()} methods manually.
*
* @param String|array $relation The array/dot-syntax relation to follow
* @return The model class of the related item
*/
function applyRelation($relation) {
// NO-OP
if(!$relation) return $this->dataClass;
if(is_string($relation)) $relation = explode(".", $relation);
$modelClass = $this->dataClass;
foreach($relation as $rel) {
$model = singleton($modelClass);
if ($component = $model->has_one($rel)) {
if(!$this->query->isJoinedTo($component)) {
$foreignKey = $model->getReverseAssociation($component);
$this->query->addLeftJoin($component, "\"$component\".\"ID\" = \"{$modelClass}\".\"{$foreignKey}ID\"");
/**
* add join clause to the component's ancestry classes so that the search filter could search on its
* ancester fields.
*/
$ancestry = ClassInfo::ancestry($component, true);
if(!empty($ancestry)){
$ancestry = array_reverse($ancestry);
foreach($ancestry as $ancestor){
if($ancestor != $component){
$this->query->addInnerJoin($ancestor, "\"$component\".\"ID\" = \"$ancestor\".\"ID\"");
$component=$ancestor;
}
}
}
}
$modelClass = $component;
} elseif ($component = $model->has_many($rel)) {
if(!$this->query->isJoinedTo($component)) {
$ancestry = $model->getClassAncestry();
$foreignKey = $model->getRemoteJoinField($rel);
$this->query->addLeftJoin($component, "\"$component\".\"{$foreignKey}\" = \"{$ancestry[0]}\".\"ID\"");
/**
* add join clause to the component's ancestry classes so that the search filter could search on its
* ancestor fields.
*/
$ancestry = ClassInfo::ancestry($component, true);
if(!empty($ancestry)){
$ancestry = array_reverse($ancestry);
foreach($ancestry as $ancestor){
if($ancestor != $component){
$this->query->addInnerJoin($ancestor, "\"$component\".\"ID\" = \"$ancestor\".\"ID\"");
$component=$ancestor;
}
}
}
}
$modelClass = $component;
} elseif ($component = $model->many_many($rel)) {
list($parentClass, $componentClass, $parentField, $componentField, $relationTable) = $component;
$parentBaseClass = ClassInfo::baseDataClass($parentClass);
$componentBaseClass = ClassInfo::baseDataClass($componentClass);
$this->query->addInnerJoin($relationTable, "\"$relationTable\".\"$parentField\" = \"$parentBaseClass\".\"ID\"");
$this->query->addLeftJoin($componentBaseClass, "\"$relationTable\".\"$componentField\" = \"$componentBaseClass\".\"ID\"");
if(ClassInfo::hasTable($componentClass)) {
$this->query->addLeftJoin($componentClass, "\"$relationTable\".\"$componentField\" = \"$componentClass\".\"ID\"");
}
$modelClass = $componentClass;
}
}
return $modelClass;
}
/**
* Removes the result of query from this query.
*
* @param DataQuery $subtractQuery
* @param string $field
*/
public function subtract(DataQuery $subtractQuery, $field='ID') {
$subSelect= $subtractQuery->getFinalisedQuery();
$fieldExpression = $this->expressionForField($field, $subSelect);
$subSelect->setSelect(array());
$subSelect->selectField($fieldExpression, $field);
$this->where($this->expressionForField($field, $this).' NOT IN ('.$subSelect->sql().')');
return $this;
}
/**
* Select the given fields from the given table.
*
* @param String $table Unquoted table name (will be escaped automatically)
* @param Array $fields Database column names (will be escaped automatically)
*/
public function selectFromTable($table, $fields) {
$table = Convert::raw2sql($table);
$fieldExpressions = array_map(create_function('$item',
"return '\"$table\".\"' . Convert::raw2sql(\$item) . '\"';"), $fields);
$this->query->setSelect($fieldExpressions);
return $this;
}
/**
* Query the given field column from the database and return as an array.
*
* @param String $field See {@link expressionForField()}.
*/
public function column($field = 'ID') {
$query = $this->getFinalisedQuery(array($field));
$originalSelect = $query->getSelect();
$fieldExpression = $this->expressionForField($field, $query);
$query->setSelect(array());
$query->selectField($fieldExpression, $field);
$this->ensureSelectContainsOrderbyColumns($query, $originalSelect);
return $query->execute()->column($field);
}
/**
* @param String $field Select statement identifier, either the unquoted column name,
* the full composite SQL statement, or the alias set through {@link SQLQquery->selectField()}.
* @param SQLQuery $query
* @return String
*/
protected function expressionForField($field, $query) {
// Special case for ID
if($field == 'ID') {
$baseClass = ClassInfo::baseDataClass($this->dataClass);
return "\"$baseClass\".\"ID\"";
} else {
return $query->expressionForField($field);
}
}
/**
* Select the given field expressions.
*
* @param $fieldExpression String The field to select (escaped SQL statement)
* @param $alias String The alias of that field (escaped SQL statement)
*/
protected function selectField($fieldExpression, $alias = null) {
$this->query->selectField($fieldExpression, $alias);
}
//// QUERY PARAMS
/**
* An arbitrary store of query parameters that can be used by decorators.
* @todo This will probably be made obsolete if we have subclasses of DataList and/or DataQuery.
*/
private $queryParams;
/**
* Set an arbitrary query parameter, that can be used by decorators to add additional meta-data to the query.
* It's expected that the $key will be namespaced, e.g, 'Versioned.stage' instead of just 'stage'.
*/
function setQueryParam($key, $value) {
$this->queryParams[$key] = $value;
}
/**
* Set an arbitrary query parameter, that can be used by decorators to add additional meta-data to the query.
*/
function getQueryParam($key) {
if(isset($this->queryParams[$key])) return $this->queryParams[$key];
else return null;
}
}