For a description of Solr grouping (also referred to as 'result grouping' or 'field collapse') see the http://wiki.apache.org/solr/FieldCollapsing Solr wiki page.
It's important to have a good understanding of the available options, as they can have have big effects on the result format.
Options
Name | Type | Default value | Description |
---|---|---|---|
queries | string | null | Queries to generate grouped results for. Separate multiple fields with commas. |
fields | string | null | Fields to generate grouped results for. Separate multiple fields with commas. |
limit | int | null | The number of results (documents) to return for each group |
offset | int | null | The offset into the document list of each group |
sort | string | null | How to sort documents within a single group |
mainresult | boolean | null | If true, the result of the first field grouping command is used as the main resultset. This way you can handle the resultdata like a normal search result, instead of the grouping result format. |
numberofgroups | boolean | null | If true, include a count of the number of groups that have matched the query |
cachepercentage | int | null | If > 0 enables grouping cache in Solr. See Solr docs for details. |
truncate | boolean | null | If true, facet counts are based on the most relevant document of each group matching the query. This param is available since Solarium 3.3 and only works with Solr 3.4 and up. |
function | string | null | Group based on the unique values of a function query. Only available in Solr 4.0+ |
facet | boolean | null | Group based on the unique values of a function query. Only available in Solr 4.0+ |
format | string | null | If 'simple', the grouped documents are presented in a single flat list. |
Examples
Grouping by field:
<?php
require(__DIR__.'/init.php');
htmlHeader();
// create a client instance
$client = new Solarium\Client($config);
// get a select query instance
$query = $client->createSelect();
$query->setRows(50);
// get grouping component and set a field to group by
$groupComponent = $query->getGrouping();
$groupComponent->addField('inStock');
// maximum number of items per group
$groupComponent->setLimit(3);
// get a group count
$groupComponent->setNumberOfGroups(true);
// this executes the query and returns the result
$resultset = $client->select($query);
$groups = $resultset->getGrouping();
foreach ($groups as $groupKey => $fieldGroup) {
echo '<h1>'.$groupKey.'</h1>';
echo 'Matches: '.$fieldGroup->getMatches().'<br/>';
echo 'Number of groups: '.$fieldGroup->getNumberOfGroups();
foreach ($fieldGroup as $valueGroup) {
echo '<h2>'.(int)$valueGroup->getValue().'</h2>';
foreach ($valueGroup as $document) {
echo '<hr/><table>';
// the documents are also iterable, to get all fields
foreach ($document as $field => $value) {
// this converts multivalue fields to a comma-separated string
if (is_array($value)) {
$value = implode(', ', $value);
}
echo '<tr><th>' . $field . '</th><td>' . $value . '</td></tr>';
}
echo '</table>';
}
}
}
htmlFooter();
Grouping by query:
<?php
require(__DIR__.'/init.php');
htmlHeader();
// create a client instance
$client = new Solarium\Client($config);
// get a select query instance
$query = $client->createSelect();
// get grouping component and create two query groups
$groupComponent = $query->getGrouping();
$groupComponent->addQuery('price:[0 TO 99.99]');
$groupComponent->addQuery('price:[100 TO *]');
// sorting inside groups
$groupComponent->setSort('price desc');
// maximum number of items per group
$groupComponent->setLimit(5);
// this executes the query and returns the result
$resultset = $client->select($query);
$groups = $resultset->getGrouping();
foreach ($groups as $groupKey => $group) {
echo '<h1>'.$groupKey.'</h1>';
foreach ($group as $document) {
echo '<hr/><table>';
// the documents are also iterable, to get all fields
foreach ($document as $field => $value) {
// this converts multivalue fields to a comma-separated string
if (is_array($value)) {
$value = implode(', ', $value);
}
echo '<tr><th>' . $field . '</th><td>' . $value . '</td></tr>';
}
echo '</table>';
}
}
htmlFooter();