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phab/src/infrastructure/query/policy/PhabricatorCursorPagedPolicyAwareQuery.php
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PhabricatorCursorPagedPolicyAwareQuery.php
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<?php
/**
* A query class which uses cursor-based paging. This paging is much more
* performant than offset-based paging in the presence of policy filtering.
*
* @task clauses Building Query Clauses
* @task appsearch Integration with ApplicationSearch
* @task customfield Integration with CustomField
* @task paging Paging
* @task order Result Ordering
* @task edgelogic Working with Edge Logic
* @task spaces Working with Spaces
*/
abstract class PhabricatorCursorPagedPolicyAwareQuery
extends PhabricatorPolicyAwareQuery {
private $afterID;
private $beforeID;
private $applicationSearchConstraints = array();
private $internalPaging;
private $orderVector;
private $groupVector;
private $builtinOrder;
private $edgeLogicConstraints = array();
private $edgeLogicConstraintsAreValid = false;
private $spacePHIDs;
private $spaceIsArchived;
private $ngrams = array();
protected function getPageCursors(array $page) {
return array(
$this->getResultCursor(head($page)),
$this->getResultCursor(last($page)),
);
}
protected function getResultCursor($object) {
if (!is_object($object)) {
throw new Exception(
pht(
'Expected object, got "%s".',
gettype($object)));
}
return $object->getID();
}
protected function nextPage(array $page) {
// See getPagingViewer() for a description of this flag.
$this->internalPaging = true;
if ($this->beforeID !== null) {
$page = array_reverse($page, $preserve_keys = true);
list($before, $after) = $this->getPageCursors($page);
$this->beforeID = $before;
} else {
list($before, $after) = $this->getPageCursors($page);
$this->afterID = $after;
}
}
final public function setAfterID($object_id) {
$this->afterID = $object_id;
return $this;
}
final protected function getAfterID() {
return $this->afterID;
}
final public function setBeforeID($object_id) {
$this->beforeID = $object_id;
return $this;
}
final protected function getBeforeID() {
return $this->beforeID;
}
protected function loadStandardPage(PhabricatorLiskDAO $table) {
$rows = $this->loadStandardPageRows($table);
return $table->loadAllFromArray($rows);
}
protected function loadStandardPageRows(PhabricatorLiskDAO $table) {
$conn = $table->establishConnection('r');
$rows = queryfx_all(
$conn,
'%Q FROM %T %Q %Q %Q %Q %Q %Q %Q',
$this->buildSelectClause($conn),
$table->getTableName(),
(string)$this->getPrimaryTableAlias(),
$this->buildJoinClause($conn),
$this->buildWhereClause($conn),
$this->buildGroupClause($conn),
$this->buildHavingClause($conn),
$this->buildOrderClause($conn),
$this->buildLimitClause($conn));
return $rows;
}
/**
* Get the viewer for making cursor paging queries.
*
* NOTE: You should ONLY use this viewer to load cursor objects while
* building paging queries.
*
* Cursor paging can happen in two ways. First, the user can request a page
* like `/stuff/?after=33`, which explicitly causes paging. Otherwise, we
* can fall back to implicit paging if we filter some results out of a
* result list because the user can't see them and need to go fetch some more
* results to generate a large enough result list.
*
* In the first case, want to use the viewer's policies to load the object.
* This prevents an attacker from figuring out information about an object
* they can't see by executing queries like `/stuff/?after=33&order=name`,
* which would otherwise give them a hint about the name of the object.
* Generally, if a user can't see an object, they can't use it to page.
*
* In the second case, we need to load the object whether the user can see
* it or not, because we need to examine new results. For example, if a user
* loads `/stuff/` and we run a query for the first 100 items that they can
* see, but the first 100 rows in the database aren't visible, we need to
* be able to issue a query for the next 100 results. If we can't load the
* cursor object, we'll fail or issue the same query over and over again.
* So, generally, internal paging must bypass policy controls.
*
* This method returns the appropriate viewer, based on the context in which
* the paging is occuring.
*
* @return PhabricatorUser Viewer for executing paging queries.
*/
final protected function getPagingViewer() {
if ($this->internalPaging) {
return PhabricatorUser::getOmnipotentUser();
} else {
return $this->getViewer();
}
}
final protected function buildLimitClause(AphrontDatabaseConnection $conn_r) {
if ($this->getRawResultLimit()) {
return qsprintf($conn_r, 'LIMIT %d', $this->getRawResultLimit());
} else {
return '';
}
}
final protected function didLoadResults(array $results) {
if ($this->beforeID) {
$results = array_reverse($results, $preserve_keys = true);
}
return $results;
}
final public function executeWithCursorPager(AphrontCursorPagerView $pager) {
$limit = $pager->getPageSize();
$this->setLimit($limit + 1);
if ($pager->getAfterID()) {
$this->setAfterID($pager->getAfterID());
} else if ($pager->getBeforeID()) {
$this->setBeforeID($pager->getBeforeID());
}
$results = $this->execute();
$count = count($results);
$sliced_results = $pager->sliceResults($results);
if ($sliced_results) {
list($before, $after) = $this->getPageCursors($sliced_results);
if ($pager->getBeforeID() || ($count > $limit)) {
$pager->setNextPageID($after);
}
if ($pager->getAfterID() ||
($pager->getBeforeID() && ($count > $limit))) {
$pager->setPrevPageID($before);
}
}
return $sliced_results;
}
/**
* Return the alias this query uses to identify the primary table.
*
* Some automatic query constructions may need to be qualified with a table
* alias if the query performs joins which make column names ambiguous. If
* this is the case, return the alias for the primary table the query
* uses; generally the object table which has `id` and `phid` columns.
*
* @return string Alias for the primary table.
*/
protected function getPrimaryTableAlias() {
return null;
}
public function newResultObject() {
return null;
}
/* -( Building Query Clauses )--------------------------------------------- */
/**
* @task clauses
*/
protected function buildSelectClause(AphrontDatabaseConnection $conn) {
$parts = $this->buildSelectClauseParts($conn);
return $this->formatSelectClause($parts);
}
/**
* @task clauses
*/
protected function buildSelectClauseParts(AphrontDatabaseConnection $conn) {
$select = array();
$alias = $this->getPrimaryTableAlias();
if ($alias) {
$select[] = qsprintf($conn, '%T.*', $alias);
} else {
$select[] = '*';
}
$select[] = $this->buildEdgeLogicSelectClause($conn);
return $select;
}
/**
* @task clauses
*/
protected function buildJoinClause(AphrontDatabaseConnection $conn) {
$joins = $this->buildJoinClauseParts($conn);
return $this->formatJoinClause($joins);
}
/**
* @task clauses
*/
protected function buildJoinClauseParts(AphrontDatabaseConnection $conn) {
$joins = array();
$joins[] = $this->buildEdgeLogicJoinClause($conn);
$joins[] = $this->buildApplicationSearchJoinClause($conn);
$joins[] = $this->buildNgramsJoinClause($conn);
return $joins;
}
/**
* @task clauses
*/
protected function buildWhereClause(AphrontDatabaseConnection $conn) {
$where = $this->buildWhereClauseParts($conn);
return $this->formatWhereClause($where);
}
/**
* @task clauses
*/
protected function buildWhereClauseParts(AphrontDatabaseConnection $conn) {
$where = array();
$where[] = $this->buildPagingClause($conn);
$where[] = $this->buildEdgeLogicWhereClause($conn);
$where[] = $this->buildSpacesWhereClause($conn);
$where[] = $this->buildNgramsWhereClause($conn);
return $where;
}
/**
* @task clauses
*/
protected function buildHavingClause(AphrontDatabaseConnection $conn) {
$having = $this->buildHavingClauseParts($conn);
return $this->formatHavingClause($having);
}
/**
* @task clauses
*/
protected function buildHavingClauseParts(AphrontDatabaseConnection $conn) {
$having = array();
$having[] = $this->buildEdgeLogicHavingClause($conn);
return $having;
}
/**
* @task clauses
*/
protected function buildGroupClause(AphrontDatabaseConnection $conn) {
if (!$this->shouldGroupQueryResultRows()) {
return '';
}
return qsprintf(
$conn,
'GROUP BY %Q',
$this->getApplicationSearchObjectPHIDColumn());
}
/**
* @task clauses
*/
protected function shouldGroupQueryResultRows() {
if ($this->shouldGroupEdgeLogicResultRows()) {
return true;
}
if ($this->getApplicationSearchMayJoinMultipleRows()) {
return true;
}
if ($this->shouldGroupNgramResultRows()) {
return true;
}
return false;
}
/* -( Paging )------------------------------------------------------------- */
/**
* @task paging
*/
protected function buildPagingClause(AphrontDatabaseConnection $conn) {
$orderable = $this->getOrderableColumns();
$vector = $this->getOrderVector();
if ($this->beforeID !== null) {
$cursor = $this->beforeID;
$reversed = true;
} else if ($this->afterID !== null) {
$cursor = $this->afterID;
$reversed = false;
} else {
// No paging is being applied to this query so we do not need to
// construct a paging clause.
return '';
}
$keys = array();
foreach ($vector as $order) {
$keys[] = $order->getOrderKey();
}
$value_map = $this->getPagingValueMap($cursor, $keys);
$columns = array();
foreach ($vector as $order) {
$key = $order->getOrderKey();
if (!array_key_exists($key, $value_map)) {
throw new Exception(
pht(
'Query "%s" failed to return a value from getPagingValueMap() '.
'for column "%s".',
get_class($this),
$key));
}
$column = $orderable[$key];
$column['value'] = $value_map[$key];
$columns[] = $column;
}
return $this->buildPagingClauseFromMultipleColumns(
$conn,
$columns,
array(
'reversed' => $reversed,
));
}
/**
* @task paging
*/
protected function getPagingValueMap($cursor, array $keys) {
return array(
'id' => $cursor,
);
}
/**
* @task paging
*/
protected function loadCursorObject($cursor) {
$query = newv(get_class($this), array())
->setViewer($this->getPagingViewer())
->withIDs(array((int)$cursor));
$this->willExecuteCursorQuery($query);
$object = $query->executeOne();
if (!$object) {
throw new Exception(
pht(
'Cursor "%s" does not identify a valid object in query "%s".',
$cursor,
get_class($this)));
}
return $object;
}
/**
* @task paging
*/
protected function willExecuteCursorQuery(
PhabricatorCursorPagedPolicyAwareQuery $query) {
return;
}
/**
* Simplifies the task of constructing a paging clause across multiple
* columns. In the general case, this looks like:
*
* A > a OR (A = a AND B > b) OR (A = a AND B = b AND C > c)
*
* To build a clause, specify the name, type, and value of each column
* to include:
*
* $this->buildPagingClauseFromMultipleColumns(
* $conn_r,
* array(
* array(
* 'table' => 't',
* 'column' => 'title',
* 'type' => 'string',
* 'value' => $cursor->getTitle(),
* 'reverse' => true,
* ),
* array(
* 'table' => 't',
* 'column' => 'id',
* 'type' => 'int',
* 'value' => $cursor->getID(),
* ),
* ),
* array(
* 'reversed' => $is_reversed,
* ));
*
* This method will then return a composable clause for inclusion in WHERE.
*
* @param AphrontDatabaseConnection Connection query will execute on.
* @param list<map> Column description dictionaries.
* @param map Additional constuction options.
* @return string Query clause.
* @task paging
*/
final protected function buildPagingClauseFromMultipleColumns(
AphrontDatabaseConnection $conn,
array $columns,
array $options) {
foreach ($columns as $column) {
PhutilTypeSpec::checkMap(
$column,
array(
'table' => 'optional string|null',
'column' => 'string',
'value' => 'wild',
'type' => 'string',
'reverse' => 'optional bool',
'unique' => 'optional bool',
'null' => 'optional string|null',
));
}
PhutilTypeSpec::checkMap(
$options,
array(
'reversed' => 'optional bool',
));
$is_query_reversed = idx($options, 'reversed', false);
$clauses = array();
$accumulated = array();
$last_key = last_key($columns);
foreach ($columns as $key => $column) {
$type = $column['type'];
$null = idx($column, 'null');
if ($column['value'] === null) {
if ($null) {
$value = null;
} else {
throw new Exception(
pht(
'Column "%s" has null value, but does not specify a null '.
'behavior.',
$key));
}
} else {
switch ($type) {
case 'int':
$value = qsprintf($conn, '%d', $column['value']);
break;
case 'float':
$value = qsprintf($conn, '%f', $column['value']);
break;
case 'string':
$value = qsprintf($conn, '%s', $column['value']);
break;
default:
throw new Exception(
pht(
'Column "%s" has unknown column type "%s".',
$column['column'],
$type));
}
}
$is_column_reversed = idx($column, 'reverse', false);
$reverse = ($is_query_reversed xor $is_column_reversed);
$clause = $accumulated;
$table_name = idx($column, 'table');
$column_name = $column['column'];
if ($table_name !== null) {
$field = qsprintf($conn, '%T.%T', $table_name, $column_name);
} else {
$field = qsprintf($conn, '%T', $column_name);
}
$parts = array();
if ($null) {
$can_page_if_null = ($null === 'head');
$can_page_if_nonnull = ($null === 'tail');
if ($reverse) {
$can_page_if_null = !$can_page_if_null;
$can_page_if_nonnull = !$can_page_if_nonnull;
}
$subclause = null;
if ($can_page_if_null && $value === null) {
$parts[] = qsprintf(
$conn,
'(%Q IS NOT NULL)',
$field);
} else if ($can_page_if_nonnull && $value !== null) {
$parts[] = qsprintf(
$conn,
'(%Q IS NULL)',
$field);
}
}
if ($value !== null) {
$parts[] = qsprintf(
$conn,
'%Q %Q %Q',
$field,
$reverse ? '>' : '<',
$value);
}
if ($parts) {
if (count($parts) > 1) {
$clause[] = '('.implode(') OR (', $parts).')';
} else {
$clause[] = head($parts);
}
}
if ($clause) {
if (count($clause) > 1) {
$clauses[] = '('.implode(') AND (', $clause).')';
} else {
$clauses[] = head($clause);
}
}
if ($value === null) {
$accumulated[] = qsprintf(
$conn,
'%Q IS NULL',
$field);
} else {
$accumulated[] = qsprintf(
$conn,
'%Q = %Q',
$field,
$value);
}
}
return '('.implode(') OR (', $clauses).')';
}
/* -( Result Ordering )---------------------------------------------------- */
/**
* Select a result ordering.
*
* This is a high-level method which selects an ordering from a predefined
* list of builtin orders, as provided by @{method:getBuiltinOrders}. These
* options are user-facing and not exhaustive, but are generally convenient
* and meaningful.
*
* You can also use @{method:setOrderVector} to specify a low-level ordering
* across individual orderable columns. This offers greater control but is
* also more involved.
*
* @param string Key of a builtin order supported by this query.
* @return this
* @task order
*/
public function setOrder($order) {
$aliases = $this->getBuiltinOrderAliasMap();
if (empty($aliases[$order])) {
throw new Exception(
pht(
'Query "%s" does not support a builtin order "%s". Supported orders '.
'are: %s.',
get_class($this),
$order,
implode(', ', array_keys($aliases))));
}
$this->builtinOrder = $aliases[$order];
$this->orderVector = null;
return $this;
}
/**
* Set a grouping order to apply before primary result ordering.
*
* This allows you to preface the query order vector with additional orders,
* so you can effect "group by" queries while still respecting "order by".
*
* This is a high-level method which works alongside @{method:setOrder}. For
* lower-level control over order vectors, use @{method:setOrderVector}.
*
* @param PhabricatorQueryOrderVector|list<string> List of order keys.
* @return this
* @task order
*/
public function setGroupVector($vector) {
$this->groupVector = $vector;
$this->orderVector = null;
return $this;
}
/**
* Get builtin orders for this class.
*
* In application UIs, we want to be able to present users with a small
* selection of meaningful order options (like "Order by Title") rather than
* an exhaustive set of column ordering options.
*
* Meaningful user-facing orders are often really orders across multiple
* columns: for example, a "title" ordering is usually implemented as a
* "title, id" ordering under the hood.
*
* Builtin orders provide a mapping from convenient, understandable
* user-facing orders to implementations.
*
* A builtin order should provide these keys:
*
* - `vector` (`list<string>`): The actual order vector to use.
* - `name` (`string`): Human-readable order name.
*
* @return map<string, wild> Map from builtin order keys to specification.
* @task order
*/
public function getBuiltinOrders() {
$orders = array(
'newest' => array(
'vector' => array('id'),
'name' => pht('Creation (Newest First)'),
'aliases' => array('created'),
),
'oldest' => array(
'vector' => array('-id'),
'name' => pht('Creation (Oldest First)'),
),
);
$object = $this->newResultObject();
if ($object instanceof PhabricatorCustomFieldInterface) {
$list = PhabricatorCustomField::getObjectFields(
$object,
PhabricatorCustomField::ROLE_APPLICATIONSEARCH);
foreach ($list->getFields() as $field) {
$index = $field->buildOrderIndex();
if (!$index) {
continue;
}
$legacy_key = 'custom:'.$field->getFieldKey();
$modern_key = $field->getModernFieldKey();
$orders[$modern_key] = array(
'vector' => array($modern_key, 'id'),
'name' => $field->getFieldName(),
'aliases' => array($legacy_key),
);
$orders['-'.$modern_key] = array(
'vector' => array('-'.$modern_key, '-id'),
'name' => pht('%s (Reversed)', $field->getFieldName()),
);
}
}
return $orders;
}
public function getBuiltinOrderAliasMap() {
$orders = $this->getBuiltinOrders();
$map = array();
foreach ($orders as $key => $order) {
$keys = array();
$keys[] = $key;
foreach (idx($order, 'aliases', array()) as $alias) {
$keys[] = $alias;
}
foreach ($keys as $alias) {
if (isset($map[$alias])) {
throw new Exception(
pht(
'Two builtin orders ("%s" and "%s") define the same key or '.
'alias ("%s"). Each order alias and key must be unique and '.
'identify a single order.',
$key,
$map[$alias],
$alias));
}
$map[$alias] = $key;
}
}
return $map;
}
/**
* Set a low-level column ordering.
*
* This is a low-level method which offers granular control over column
* ordering. In most cases, applications can more easily use
* @{method:setOrder} to choose a high-level builtin order.
*
* To set an order vector, specify a list of order keys as provided by
* @{method:getOrderableColumns}.
*
* @param PhabricatorQueryOrderVector|list<string> List of order keys.
* @return this
* @task order
*/
public function setOrderVector($vector) {
$vector = PhabricatorQueryOrderVector::newFromVector($vector);
$orderable = $this->getOrderableColumns();
// Make sure that all the components identify valid columns.
$unique = array();
foreach ($vector as $order) {
$key = $order->getOrderKey();
if (empty($orderable[$key])) {
$valid = implode(', ', array_keys($orderable));
throw new Exception(
pht(
'This query ("%s") does not support sorting by order key "%s". '.
'Supported orders are: %s.',
get_class($this),
$key,
$valid));
}
$unique[$key] = idx($orderable[$key], 'unique', false);
}
// Make sure that the last column is unique so that this is a strong
// ordering which can be used for paging.
$last = last($unique);
if ($last !== true) {
throw new Exception(
pht(
'Order vector "%s" is invalid: the last column in an order must '.
'be a column with unique values, but "%s" is not unique.',
$vector->getAsString(),
last_key($unique)));
}
// Make sure that other columns are not unique; an ordering like "id, name"
// does not make sense because only "id" can ever have an effect.
array_pop($unique);
foreach ($unique as $key => $is_unique) {
if ($is_unique) {
throw new Exception(
pht(
'Order vector "%s" is invalid: only the last column in an order '.
'may be unique, but "%s" is a unique column and not the last '.
'column in the order.',
$vector->getAsString(),
$key));
}
}
$this->orderVector = $vector;
return $this;
}
/**
* Get the effective order vector.
*
* @return PhabricatorQueryOrderVector Effective vector.
* @task order
*/
protected function getOrderVector() {
if (!$this->orderVector) {
if ($this->builtinOrder !== null) {
$builtin_order = idx($this->getBuiltinOrders(), $this->builtinOrder);
$vector = $builtin_order['vector'];
} else {
$vector = $this->getDefaultOrderVector();
}
if ($this->groupVector) {
$group = PhabricatorQueryOrderVector::newFromVector($this->groupVector);
$group->appendVector($vector);
$vector = $group;
}
$vector = PhabricatorQueryOrderVector::newFromVector($vector);
// We call setOrderVector() here to apply checks to the default vector.
// This catches any errors in the implementation.
$this->setOrderVector($vector);
}
return $this->orderVector;
}
/**
* @task order
*/
protected function getDefaultOrderVector() {
return array('id');
}
/**
* @task order
*/
public function getOrderableColumns() {
$cache = PhabricatorCaches::getRequestCache();
$class = get_class($this);
$cache_key = 'query.orderablecolumns.'.$class;
$columns = $cache->getKey($cache_key);
if ($columns !== null) {
return $columns;
}
$columns = array(
'id' => array(
'table' => $this->getPrimaryTableAlias(),
'column' => 'id',
'reverse' => false,
'type' => 'int',
'unique' => true,
),
);
$object = $this->newResultObject();
if ($object instanceof PhabricatorCustomFieldInterface) {
$list = PhabricatorCustomField::getObjectFields(
$object,
PhabricatorCustomField::ROLE_APPLICATIONSEARCH);
foreach ($list->getFields() as $field) {
$index = $field->buildOrderIndex();
if (!$index) {
continue;
}
$digest = $field->getFieldIndex();
$key = $field->getModernFieldKey();
$columns[$key] = array(
'table' => 'appsearch_order_'.$digest,
'column' => 'indexValue',
'type' => $index->getIndexValueType(),
'null' => 'tail',
'customfield' => true,
'customfield.index.table' => $index->getTableName(),
'customfield.index.key' => $digest,
);
}
}
$cache->setKey($cache_key, $columns);
return $columns;
}
/**
* @task order
*/
final protected function buildOrderClause(AphrontDatabaseConnection $conn) {
$orderable = $this->getOrderableColumns();
$vector = $this->getOrderVector();
$parts = array();
foreach ($vector as $order) {
$part = $orderable[$order->getOrderKey()];
if ($order->getIsReversed()) {
$part['reverse'] = !idx($part, 'reverse', false);
}
$parts[] = $part;
}
return $this->formatOrderClause($conn, $parts);
}
/**
* @task order
*/
protected function formatOrderClause(
AphrontDatabaseConnection $conn,
array $parts) {
$is_query_reversed = false;
if ($this->getBeforeID()) {
$is_query_reversed = !$is_query_reversed;
}
$sql = array();
foreach ($parts as $key => $part) {
$is_column_reversed = !empty($part['reverse']);
$descending = true;
if ($is_query_reversed) {
$descending = !$descending;
}
if ($is_column_reversed) {
$descending = !$descending;
}
$table = idx($part, 'table');
$column = $part['column'];
if ($table !== null) {
$field = qsprintf($conn, '%T.%T', $table, $column);
} else {
$field = qsprintf($conn, '%T', $column);
}
$null = idx($part, 'null');
if ($null) {
switch ($null) {
case 'head':
$null_field = qsprintf($conn, '(%Q IS NULL)', $field);
break;
case 'tail':
$null_field = qsprintf($conn, '(%Q IS NOT NULL)', $field);
break;
default:
throw new Exception(
pht(
'NULL value "%s" is invalid. Valid values are "head" and '.
'"tail".',
$null));
}
if ($descending) {
$sql[] = qsprintf($conn, '%Q DESC', $null_field);
} else {
$sql[] = qsprintf($conn, '%Q ASC', $null_field);
}
}
if ($descending) {
$sql[] = qsprintf($conn, '%Q DESC', $field);
} else {
$sql[] = qsprintf($conn, '%Q ASC', $field);
}
}
return qsprintf($conn, 'ORDER BY %Q', implode(', ', $sql));
}
/* -( Application Search )------------------------------------------------- */
/**
* Constrain the query with an ApplicationSearch index, requiring field values
* contain at least one of the values in a set.
*
* This constraint can build the most common types of queries, like:
*
* - Find users with shirt sizes "X" or "XL".
* - Find shoes with size "13".
*
* @param PhabricatorCustomFieldIndexStorage Table where the index is stored.
* @param string|list<string> One or more values to filter by.
* @return this
* @task appsearch
*/
public function withApplicationSearchContainsConstraint(
PhabricatorCustomFieldIndexStorage $index,
$value) {
$this->applicationSearchConstraints[] = array(
'type' => $index->getIndexValueType(),
'cond' => '=',
'table' => $index->getTableName(),
'index' => $index->getIndexKey(),
'value' => $value,
);
return $this;
}
/**
* Constrain the query with an ApplicationSearch index, requiring values
* exist in a given range.
*
* This constraint is useful for expressing date ranges:
*
* - Find events between July 1st and July 7th.
*
* The ends of the range are inclusive, so a `$min` of `3` and a `$max` of
* `5` will match fields with values `3`, `4`, or `5`. Providing `null` for
* either end of the range will leave that end of the constraint open.
*
* @param PhabricatorCustomFieldIndexStorage Table where the index is stored.
* @param int|null Minimum permissible value, inclusive.
* @param int|null Maximum permissible value, inclusive.
* @return this
* @task appsearch
*/
public function withApplicationSearchRangeConstraint(
PhabricatorCustomFieldIndexStorage $index,
$min,
$max) {
$index_type = $index->getIndexValueType();
if ($index_type != 'int') {
throw new Exception(
pht(
'Attempting to apply a range constraint to a field with index type '.
'"%s", expected type "%s".',
$index_type,
'int'));
}
$this->applicationSearchConstraints[] = array(
'type' => $index->getIndexValueType(),
'cond' => 'range',
'table' => $index->getTableName(),
'index' => $index->getIndexKey(),
'value' => array($min, $max),
);
return $this;
}
/**
* Get the name of the query's primary object PHID column, for constructing
* JOIN clauses. Normally (and by default) this is just `"phid"`, but it may
* be something more exotic.
*
* See @{method:getPrimaryTableAlias} if the column needs to be qualified with
* a table alias.
*
* @return string Column name.
* @task appsearch
*/
protected function getApplicationSearchObjectPHIDColumn() {
if ($this->getPrimaryTableAlias()) {
$prefix = $this->getPrimaryTableAlias().'.';
} else {
$prefix = '';
}
return $prefix.'phid';
}
/**
* Determine if the JOINs built by ApplicationSearch might cause each primary
* object to return multiple result rows. Generally, this means the query
* needs an extra GROUP BY clause.
*
* @return bool True if the query may return multiple rows for each object.
* @task appsearch
*/
protected function getApplicationSearchMayJoinMultipleRows() {
foreach ($this->applicationSearchConstraints as $constraint) {
$type = $constraint['type'];
$value = $constraint['value'];
$cond = $constraint['cond'];
switch ($cond) {
case '=':
switch ($type) {
case 'string':
case 'int':
if (count((array)$value) > 1) {
return true;
}
break;
default:
throw new Exception(pht('Unknown index type "%s"!', $type));
}
break;
case 'range':
// NOTE: It's possible to write a custom field where multiple rows
// match a range constraint, but we don't currently ship any in the
// upstream and I can't immediately come up with cases where this
// would make sense.
break;
default:
throw new Exception(pht('Unknown constraint condition "%s"!', $cond));
}
}
return false;
}
/**
* Construct a GROUP BY clause appropriate for ApplicationSearch constraints.
*
* @param AphrontDatabaseConnection Connection executing the query.
* @return string Group clause.
* @task appsearch
*/
protected function buildApplicationSearchGroupClause(
AphrontDatabaseConnection $conn_r) {
if ($this->getApplicationSearchMayJoinMultipleRows()) {
return qsprintf(
$conn_r,
'GROUP BY %Q',
$this->getApplicationSearchObjectPHIDColumn());
} else {
return '';
}
}
/**
* Construct a JOIN clause appropriate for applying ApplicationSearch
* constraints.
*
* @param AphrontDatabaseConnection Connection executing the query.
* @return string Join clause.
* @task appsearch
*/
protected function buildApplicationSearchJoinClause(
AphrontDatabaseConnection $conn_r) {
$joins = array();
foreach ($this->applicationSearchConstraints as $key => $constraint) {
$table = $constraint['table'];
$alias = 'appsearch_'.$key;
$index = $constraint['index'];
$cond = $constraint['cond'];
$phid_column = $this->getApplicationSearchObjectPHIDColumn();
switch ($cond) {
case '=':
$type = $constraint['type'];
switch ($type) {
case 'string':
$constraint_clause = qsprintf(
$conn_r,
'%T.indexValue IN (%Ls)',
$alias,
(array)$constraint['value']);
break;
case 'int':
$constraint_clause = qsprintf(
$conn_r,
'%T.indexValue IN (%Ld)',
$alias,
(array)$constraint['value']);
break;
default:
throw new Exception(pht('Unknown index type "%s"!', $type));
}
$joins[] = qsprintf(
$conn_r,
'JOIN %T %T ON %T.objectPHID = %Q
AND %T.indexKey = %s
AND (%Q)',
$table,
$alias,
$alias,
$phid_column,
$alias,
$index,
$constraint_clause);
break;
case 'range':
list($min, $max) = $constraint['value'];
if (($min === null) && ($max === null)) {
// If there's no actual range constraint, just move on.
break;
}
if ($min === null) {
$constraint_clause = qsprintf(
$conn_r,
'%T.indexValue <= %d',
$alias,
$max);
} else if ($max === null) {
$constraint_clause = qsprintf(
$conn_r,
'%T.indexValue >= %d',
$alias,
$min);
} else {
$constraint_clause = qsprintf(
$conn_r,
'%T.indexValue BETWEEN %d AND %d',
$alias,
$min,
$max);
}
$joins[] = qsprintf(
$conn_r,
'JOIN %T %T ON %T.objectPHID = %Q
AND %T.indexKey = %s
AND (%Q)',
$table,
$alias,
$alias,
$phid_column,
$alias,
$index,
$constraint_clause);
break;
default:
throw new Exception(pht('Unknown constraint condition "%s"!', $cond));
}
}
$phid_column = $this->getApplicationSearchObjectPHIDColumn();
$orderable = $this->getOrderableColumns();
$vector = $this->getOrderVector();
foreach ($vector as $order) {
$spec = $orderable[$order->getOrderKey()];
if (empty($spec['customfield'])) {
continue;
}
$table = $spec['customfield.index.table'];
$alias = $spec['table'];
$key = $spec['customfield.index.key'];
$joins[] = qsprintf(
$conn_r,
'LEFT JOIN %T %T ON %T.objectPHID = %Q
AND %T.indexKey = %s',
$table,
$alias,
$alias,
$phid_column,
$alias,
$key);
}
return implode(' ', $joins);
}
/* -( Integration with CustomField )--------------------------------------- */
/**
* @task customfield
*/
protected function getPagingValueMapForCustomFields(
PhabricatorCustomFieldInterface $object) {
// We have to get the current field values on the cursor object.
$fields = PhabricatorCustomField::getObjectFields(
$object,
PhabricatorCustomField::ROLE_APPLICATIONSEARCH);
$fields->setViewer($this->getViewer());
$fields->readFieldsFromStorage($object);
$map = array();
foreach ($fields->getFields() as $field) {
$map['custom:'.$field->getFieldKey()] = $field->getValueForStorage();
}
return $map;
}
/**
* @task customfield
*/
protected function isCustomFieldOrderKey($key) {
$prefix = 'custom:';
return !strncmp($key, $prefix, strlen($prefix));
}
/* -( Ngrams )------------------------------------------------------------- */
protected function withNgramsConstraint(
PhabricatorSearchNgrams $index,
$value) {
if (strlen($value)) {
$this->ngrams[] = array(
'index' => $index,
'value' => $value,
'length' => count(phutil_utf8v($value)),
);
}
return $this;
}
protected function buildNgramsJoinClause(AphrontDatabaseConnection $conn) {
$flat = array();
foreach ($this->ngrams as $spec) {
$index = $spec['index'];
$value = $spec['value'];
$length = $spec['length'];
if ($length >= 3) {
$ngrams = $index->getNgramsFromString($value, 'query');
$prefix = false;
} else if ($length == 2) {
$ngrams = $index->getNgramsFromString($value, 'prefix');
$prefix = false;
} else {
$ngrams = array(' '.$value);
$prefix = true;
}
foreach ($ngrams as $ngram) {
$flat[] = array(
'table' => $index->getTableName(),
'ngram' => $ngram,
'prefix' => $prefix,
);
}
}
// MySQL only allows us to join a maximum of 61 tables per query. Each
// ngram is going to cost us a join toward that limit, so if the user
// specified a very long query string, just pick 16 of the ngrams
// at random.
if (count($flat) > 16) {
shuffle($flat);
$flat = array_slice($flat, 0, 16);
}
$alias = $this->getPrimaryTableAlias();
if ($alias) {
$id_column = qsprintf($conn, '%T.%T', $alias, 'id');
} else {
$id_column = qsprintf($conn, '%T', 'id');
}
$idx = 1;
$joins = array();
foreach ($flat as $spec) {
$table = $spec['table'];
$ngram = $spec['ngram'];
$prefix = $spec['prefix'];
$alias = 'ngm'.$idx++;
if ($prefix) {
$joins[] = qsprintf(
$conn,
'JOIN %T %T ON %T.objectID = %Q AND %T.ngram LIKE %>',
$table,
$alias,
$alias,
$id_column,
$alias,
$ngram);
} else {
$joins[] = qsprintf(
$conn,
'JOIN %T %T ON %T.objectID = %Q AND %T.ngram = %s',
$table,
$alias,
$alias,
$id_column,
$alias,
$ngram);
}
}
return $joins;
}
protected function buildNgramsWhereClause(AphrontDatabaseConnection $conn) {
$where = array();
foreach ($this->ngrams as $ngram) {
$index = $ngram['index'];
$value = $ngram['value'];
$column = $index->getColumnName();
$alias = $this->getPrimaryTableAlias();
if ($alias) {
$column = qsprintf($conn, '%T.%T', $alias, $column);
} else {
$column = qsprintf($conn, '%T', $column);
}
$tokens = $index->tokenizeString($value);
foreach ($tokens as $token) {
$where[] = qsprintf(
$conn,
'%Q LIKE %~',
$column,
$token);
}
}
return $where;
}
protected function shouldGroupNgramResultRows() {
return (bool)$this->ngrams;
}
/* -( Edge Logic )--------------------------------------------------------- */
/**
* Convenience method for specifying edge logic constraints with a list of
* PHIDs.
*
* @param const Edge constant.
* @param const Constraint operator.
* @param list<phid> List of PHIDs.
* @return this
* @task edgelogic
*/
public function withEdgeLogicPHIDs($edge_type, $operator, array $phids) {
$constraints = array();
foreach ($phids as $phid) {
$constraints[] = new PhabricatorQueryConstraint($operator, $phid);
}
return $this->withEdgeLogicConstraints($edge_type, $constraints);
}
/**
* @task edgelogic
*/
public function withEdgeLogicConstraints($edge_type, array $constraints) {
assert_instances_of($constraints, 'PhabricatorQueryConstraint');
$constraints = mgroup($constraints, 'getOperator');
foreach ($constraints as $operator => $list) {
foreach ($list as $item) {
$this->edgeLogicConstraints[$edge_type][$operator][] = $item;
}
}
$this->edgeLogicConstraintsAreValid = false;
return $this;
}
/**
* @task edgelogic
*/
public function buildEdgeLogicSelectClause(AphrontDatabaseConnection $conn) {
$select = array();
$this->validateEdgeLogicConstraints();
foreach ($this->edgeLogicConstraints as $type => $constraints) {
foreach ($constraints as $operator => $list) {
$alias = $this->getEdgeLogicTableAlias($operator, $type);
switch ($operator) {
case PhabricatorQueryConstraint::OPERATOR_AND:
if (count($list) > 1) {
$select[] = qsprintf(
$conn,
'COUNT(DISTINCT(%T.dst)) %T',
$alias,
$this->buildEdgeLogicTableAliasCount($alias));
}
break;
case PhabricatorQueryConstraint::OPERATOR_ANCESTOR:
// This is tricky. We have a query which specifies multiple
// projects, each of which may have an arbitrarily large number
// of descendants.
// Suppose the projects are "Engineering" and "Operations", and
// "Engineering" has subprojects X, Y and Z.
// We first use `FIELD(dst, X, Y, Z)` to produce a 0 if a row
// is not part of Engineering at all, or some number other than
// 0 if it is.
// Then we use `IF(..., idx, NULL)` to convert the 0 to a NULL and
// any other value to an index (say, 1) for the ancestor.
// We build these up for every ancestor, then use `COALESCE(...)`
// to select the non-null one, giving us an ancestor which this
// row is a member of.
// From there, we use `COUNT(DISTINCT(...))` to make sure that
// each result row is a member of all ancestors.
if (count($list) > 1) {
$idx = 1;
$parts = array();
foreach ($list as $constraint) {
$parts[] = qsprintf(
$conn,
'IF(FIELD(%T.dst, %Ls) != 0, %d, NULL)',
$alias,
(array)$constraint->getValue(),
$idx++);
}
$parts = implode(', ', $parts);
$select[] = qsprintf(
$conn,
'COUNT(DISTINCT(COALESCE(%Q))) %T',
$parts,
$this->buildEdgeLogicTableAliasAncestor($alias));
}
break;
default:
break;
}
}
}
return $select;
}
/**
* @task edgelogic
*/
public function buildEdgeLogicJoinClause(AphrontDatabaseConnection $conn) {
$edge_table = PhabricatorEdgeConfig::TABLE_NAME_EDGE;
$phid_column = $this->getApplicationSearchObjectPHIDColumn();
$joins = array();
foreach ($this->edgeLogicConstraints as $type => $constraints) {
$op_null = PhabricatorQueryConstraint::OPERATOR_NULL;
$has_null = isset($constraints[$op_null]);
foreach ($constraints as $operator => $list) {
$alias = $this->getEdgeLogicTableAlias($operator, $type);
$phids = array();
foreach ($list as $constraint) {
$value = (array)$constraint->getValue();
foreach ($value as $v) {
$phids[$v] = $v;
}
}
$phids = array_keys($phids);
switch ($operator) {
case PhabricatorQueryConstraint::OPERATOR_NOT:
$joins[] = qsprintf(
$conn,
'LEFT JOIN %T %T ON %Q = %T.src AND %T.type = %d
AND %T.dst IN (%Ls)',
$edge_table,
$alias,
$phid_column,
$alias,
$alias,
$type,
$alias,
$phids);
break;
case PhabricatorQueryConstraint::OPERATOR_ANCESTOR:
case PhabricatorQueryConstraint::OPERATOR_AND:
case PhabricatorQueryConstraint::OPERATOR_OR:
// If we're including results with no matches, we have to degrade
// this to a LEFT join. We'll use WHERE to select matching rows
// later.
if ($has_null) {
$join_type = 'LEFT';
} else {
$join_type = '';
}
$joins[] = qsprintf(
$conn,
'%Q JOIN %T %T ON %Q = %T.src AND %T.type = %d
AND %T.dst IN (%Ls)',
$join_type,
$edge_table,
$alias,
$phid_column,
$alias,
$alias,
$type,
$alias,
$phids);
break;
case PhabricatorQueryConstraint::OPERATOR_NULL:
$joins[] = qsprintf(
$conn,
'LEFT JOIN %T %T ON %Q = %T.src AND %T.type = %d',
$edge_table,
$alias,
$phid_column,
$alias,
$alias,
$type);
break;
}
}
}
return $joins;
}
/**
* @task edgelogic
*/
public function buildEdgeLogicWhereClause(AphrontDatabaseConnection $conn) {
$where = array();
foreach ($this->edgeLogicConstraints as $type => $constraints) {
$full = array();
$null = array();
$op_null = PhabricatorQueryConstraint::OPERATOR_NULL;
$has_null = isset($constraints[$op_null]);
foreach ($constraints as $operator => $list) {
$alias = $this->getEdgeLogicTableAlias($operator, $type);
switch ($operator) {
case PhabricatorQueryConstraint::OPERATOR_NOT:
$full[] = qsprintf(
$conn,
'%T.dst IS NULL',
$alias);
break;
case PhabricatorQueryConstraint::OPERATOR_AND:
case PhabricatorQueryConstraint::OPERATOR_OR:
if ($has_null) {
$full[] = qsprintf(
$conn,
'%T.dst IS NOT NULL',
$alias);
}
break;
case PhabricatorQueryConstraint::OPERATOR_NULL:
$null[] = qsprintf(
$conn,
'%T.dst IS NULL',
$alias);
break;
}
}
if ($full && $null) {
$full = $this->formatWhereSubclause($full);
$null = $this->formatWhereSubclause($null);
$where[] = qsprintf($conn, '(%Q OR %Q)', $full, $null);
} else if ($full) {
foreach ($full as $condition) {
$where[] = $condition;
}
} else if ($null) {
foreach ($null as $condition) {
$where[] = $condition;
}
}
}
return $where;
}
/**
* @task edgelogic
*/
public function buildEdgeLogicHavingClause(AphrontDatabaseConnection $conn) {
$having = array();
foreach ($this->edgeLogicConstraints as $type => $constraints) {
foreach ($constraints as $operator => $list) {
$alias = $this->getEdgeLogicTableAlias($operator, $type);
switch ($operator) {
case PhabricatorQueryConstraint::OPERATOR_AND:
if (count($list) > 1) {
$having[] = qsprintf(
$conn,
'%T = %d',
$this->buildEdgeLogicTableAliasCount($alias),
count($list));
}
break;
case PhabricatorQueryConstraint::OPERATOR_ANCESTOR:
if (count($list) > 1) {
$having[] = qsprintf(
$conn,
'%T = %d',
$this->buildEdgeLogicTableAliasAncestor($alias),
count($list));
}
break;
}
}
}
return $having;
}
/**
* @task edgelogic
*/
public function shouldGroupEdgeLogicResultRows() {
foreach ($this->edgeLogicConstraints as $type => $constraints) {
foreach ($constraints as $operator => $list) {
switch ($operator) {
case PhabricatorQueryConstraint::OPERATOR_NOT:
case PhabricatorQueryConstraint::OPERATOR_AND:
case PhabricatorQueryConstraint::OPERATOR_OR:
case PhabricatorQueryConstraint::OPERATOR_ANCESTOR:
if (count($list) > 1) {
return true;
}
break;
case PhabricatorQueryConstraint::OPERATOR_NULL:
return true;
}
}
}
return false;
}
/**
* @task edgelogic
*/
private function getEdgeLogicTableAlias($operator, $type) {
return 'edgelogic_'.$operator.'_'.$type;
}
/**
* @task edgelogic
*/
private function buildEdgeLogicTableAliasCount($alias) {
return $alias.'_count';
}
/**
* @task edgelogic
*/
private function buildEdgeLogicTableAliasAncestor($alias) {
return $alias.'_ancestor';
}
/**
* Select certain edge logic constraint values.
*
* @task edgelogic
*/
protected function getEdgeLogicValues(
array $edge_types,
array $operators) {
$values = array();
$constraint_lists = $this->edgeLogicConstraints;
if ($edge_types) {
$constraint_lists = array_select_keys($constraint_lists, $edge_types);
}
foreach ($constraint_lists as $type => $constraints) {
if ($operators) {
$constraints = array_select_keys($constraints, $operators);
}
foreach ($constraints as $operator => $list) {
foreach ($list as $constraint) {
$value = (array)$constraint->getValue();
foreach ($value as $v) {
$values[] = $v;
}
}
}
}
return $values;
}
/**
* Validate edge logic constraints for the query.
*
* @return this
* @task edgelogic
*/
private function validateEdgeLogicConstraints() {
if ($this->edgeLogicConstraintsAreValid) {
return $this;
}
foreach ($this->edgeLogicConstraints as $type => $constraints) {
foreach ($constraints as $operator => $list) {
switch ($operator) {
case PhabricatorQueryConstraint::OPERATOR_EMPTY:
throw new PhabricatorEmptyQueryException(
pht('This query specifies an empty constraint.'));
}
}
}
// This should probably be more modular, eventually, but we only do
// project-based edge logic today.
$project_phids = $this->getEdgeLogicValues(
array(
PhabricatorProjectObjectHasProjectEdgeType::EDGECONST,
),
array(
PhabricatorQueryConstraint::OPERATOR_AND,
PhabricatorQueryConstraint::OPERATOR_OR,
PhabricatorQueryConstraint::OPERATOR_NOT,
PhabricatorQueryConstraint::OPERATOR_ANCESTOR,
));
if ($project_phids) {
$projects = id(new PhabricatorProjectQuery())
->setViewer($this->getViewer())
->setParentQuery($this)
->withPHIDs($project_phids)
->execute();
$projects = mpull($projects, null, 'getPHID');
foreach ($project_phids as $phid) {
if (empty($projects[$phid])) {
throw new PhabricatorEmptyQueryException(
pht(
'This query is constrained by a project you do not have '.
'permission to see.'));
}
}
}
$this->edgeLogicConstraintsAreValid = true;
return $this;
}
/* -( Spaces )------------------------------------------------------------- */
/**
* Constrain the query to return results from only specific Spaces.
*
* Pass a list of Space PHIDs, or `null` to represent the default space. Only
* results in those Spaces will be returned.
*
* Queries are always constrained to include only results from spaces the
* viewer has access to.
*
* @param list<phid|null>
* @task spaces
*/
public function withSpacePHIDs(array $space_phids) {
$object = $this->newResultObject();
if (!$object) {
throw new Exception(
pht(
'This query (of class "%s") does not implement newResultObject(), '.
'but must implement this method to enable support for Spaces.',
get_class($this)));
}
if (!($object instanceof PhabricatorSpacesInterface)) {
throw new Exception(
pht(
'This query (of class "%s") returned an object of class "%s" from '.
'getNewResultObject(), but it does not implement the required '.
'interface ("%s"). Objects must implement this interface to enable '.
'Spaces support.',
get_class($this),
get_class($object),
'PhabricatorSpacesInterface'));
}
$this->spacePHIDs = $space_phids;
return $this;
}
public function withSpaceIsArchived($archived) {
$this->spaceIsArchived = $archived;
return $this;
}
/**
* Constrain the query to include only results in valid Spaces.
*
* This method builds part of a WHERE clause which considers the spaces the
* viewer has access to see with any explicit constraint on spaces added by
* @{method:withSpacePHIDs}.
*
* @param AphrontDatabaseConnection Database connection.
* @return string Part of a WHERE clause.
* @task spaces
*/
private function buildSpacesWhereClause(AphrontDatabaseConnection $conn) {
$object = $this->newResultObject();
if (!$object) {
return null;
}
if (!($object instanceof PhabricatorSpacesInterface)) {
return null;
}
$viewer = $this->getViewer();
// If we have an omnipotent viewer and no formal space constraints, don't
// emit a clause. This primarily enables older migrations to run cleanly,
// without fataling because they try to match a `spacePHID` column which
// does not exist yet. See T8743, T8746.
if ($viewer->isOmnipotent()) {
if ($this->spaceIsArchived === null && $this->spacePHIDs === null) {
return null;
}
}
$space_phids = array();
$include_null = false;
$all = PhabricatorSpacesNamespaceQuery::getAllSpaces();
if (!$all) {
// If there are no spaces at all, implicitly give the viewer access to
// the default space.
$include_null = true;
} else {
// Otherwise, give them access to the spaces they have permission to
// see.
$viewer_spaces = PhabricatorSpacesNamespaceQuery::getViewerSpaces(
$viewer);
foreach ($viewer_spaces as $viewer_space) {
if ($this->spaceIsArchived !== null) {
if ($viewer_space->getIsArchived() != $this->spaceIsArchived) {
continue;
}
}
$phid = $viewer_space->getPHID();
$space_phids[$phid] = $phid;
if ($viewer_space->getIsDefaultNamespace()) {
$include_null = true;
}
}
}
// If we have additional explicit constraints, evaluate them now.
if ($this->spacePHIDs !== null) {
$explicit = array();
$explicit_null = false;
foreach ($this->spacePHIDs as $phid) {
if ($phid === null) {
$space = PhabricatorSpacesNamespaceQuery::getDefaultSpace();
} else {
$space = idx($all, $phid);
}
if ($space) {
$phid = $space->getPHID();
$explicit[$phid] = $phid;
if ($space->getIsDefaultNamespace()) {
$explicit_null = true;
}
}
}
// If the viewer can see the default space but it isn't on the explicit
// list of spaces to query, don't match it.
if ($include_null && !$explicit_null) {
$include_null = false;
}
// Include only the spaces common to the viewer and the constraints.
$space_phids = array_intersect_key($space_phids, $explicit);
}
if (!$space_phids && !$include_null) {
if ($this->spacePHIDs === null) {
throw new PhabricatorEmptyQueryException(
pht('You do not have access to any spaces.'));
} else {
throw new PhabricatorEmptyQueryException(
pht(
'You do not have access to any of the spaces this query '.
'is constrained to.'));
}
}
$alias = $this->getPrimaryTableAlias();
if ($alias) {
$col = qsprintf($conn, '%T.spacePHID', $alias);
} else {
$col = 'spacePHID';
}
if ($space_phids && $include_null) {
return qsprintf(
$conn,
'(%Q IN (%Ls) OR %Q IS NULL)',
$col,
$space_phids,
$col);
} else if ($space_phids) {
return qsprintf(
$conn,
'%Q IN (%Ls)',
$col,
$space_phids);
} else {
return qsprintf(
$conn,
'%Q IS NULL',
$col);
}
}
}
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