SelectSubqueryTest.php
Same filename in other branches
Namespace
Drupal\KernelTests\Core\DatabaseFile
-
core/
tests/ Drupal/ KernelTests/ Core/ Database/ SelectSubqueryTest.php
View source
<?php
declare (strict_types=1);
namespace Drupal\KernelTests\Core\Database;
/**
* Tests the Select query builder.
*
* @group Database
*/
class SelectSubqueryTest extends DatabaseTestBase {
/**
* Tests that we can use a subquery in a FROM clause.
*/
public function testFromSubquerySelect() : void {
// Create a subquery, which is just a normal query object.
$subquery = $this->connection
->select('test_task', 'tt');
$subquery->addField('tt', 'pid', 'pid');
$subquery->addField('tt', 'task', 'task');
$subquery->condition('priority', 1);
for ($i = 0; $i < 2; $i++) {
// Create another query that joins against the virtual table resulting
// from the subquery.
$select = $this->connection
->select($subquery, 'tt2');
$select->join('test', 't', '[t].[id] = [tt2].[pid]');
$select->addField('t', 'name');
if ($i) {
// Use a different number of conditions here to confuse the subquery
// placeholder counter, testing https://www.drupal.org/node/1112854.
$select->condition('name', 'John');
}
$select->condition('task', 'code');
// The resulting query should be equivalent to:
// @code
// SELECT t.name
// FROM (SELECT tt.pid AS pid, tt.task AS task FROM test_task tt WHERE priority=1) tt
// INNER JOIN test t ON t.id=tt.pid
// WHERE tt.task = 'code'
// @endcode
$people = $select->execute()
->fetchCol();
$this->assertCount(1, $people, 'Returned the correct number of rows.');
}
}
/**
* Tests that we can use a subquery in a FROM clause with a LIMIT.
*/
public function testFromSubquerySelectWithLimit() : void {
// Create a subquery, which is just a normal query object.
$subquery = $this->connection
->select('test_task', 'tt');
$subquery->addField('tt', 'pid', 'pid');
$subquery->addField('tt', 'task', 'task');
$subquery->orderBy('priority', 'DESC');
$subquery->range(0, 1);
// Create another query that joins against the virtual table resulting
// from the subquery.
$select = $this->connection
->select($subquery, 'tt2');
$select->join('test', 't', '[t].[id] = [tt2].[pid]');
$select->addField('t', 'name');
// The resulting query should be equivalent to:
// @code
// SELECT t.name
// FROM (SELECT tt.pid AS pid, tt.task AS task FROM test_task tt ORDER BY priority DESC LIMIT 1 OFFSET 0) tt
// INNER JOIN test t ON t.id=tt.pid
// @endcode
$people = $select->execute()
->fetchCol();
$this->assertCount(1, $people, 'Returned the correct number of rows.');
}
/**
* Tests that we can use a subquery with an IN operator in a WHERE clause.
*/
public function testConditionSubquerySelect() : void {
// Create a subquery, which is just a normal query object.
$subquery = $this->connection
->select('test_task', 'tt');
$subquery->addField('tt', 'pid', 'pid');
$subquery->condition('tt.priority', 1);
// Create another query that joins against the virtual table resulting
// from the subquery.
$select = $this->connection
->select('test_task', 'tt2');
$select->addField('tt2', 'task');
$select->condition('tt2.pid', $subquery, 'IN');
// The resulting query should be equivalent to:
// SELECT tt2.name
// FROM test tt2
// WHERE tt2.pid IN (SELECT tt.pid AS pid FROM test_task tt WHERE tt.priority=1)
$people = $select->execute()
->fetchCol();
$this->assertCount(5, $people, 'Returned the correct number of rows.');
}
/**
* Tests we can use a subquery with a relational operator in a WHERE clause.
*/
public function testConditionSubquerySelect2() : void {
// Create a subquery, which is just a normal query object.
$subquery = $this->connection
->select('test', 't2');
$subquery->addExpression('AVG([t2].[age])');
// Create another query that adds a clause using the subquery.
$select = $this->connection
->select('test', 't');
$select->addField('t', 'name');
$select->condition('t.age', $subquery, '<');
// The resulting query should be equivalent to:
// SELECT t.name
// FROM test t
// WHERE t.age < (SELECT AVG(t2.age) FROM test t2)
$people = $select->execute()
->fetchCol();
$this->assertEqualsCanonicalizing([
'John',
'Paul',
], $people, 'Returned Paul and John.');
}
/**
* Tests we can use 2 subqueries with a relational operator in a WHERE clause.
*/
public function testConditionSubquerySelect3() : void {
// Create subquery 1, which is just a normal query object.
$subquery1 = $this->connection
->select('test_task', 'tt');
$subquery1->addExpression('AVG([tt].[priority])');
$subquery1->where('[tt].[pid] = [t].[id]');
// Create subquery 2, which is just a normal query object.
$subquery2 = $this->connection
->select('test_task', 'tt2');
$subquery2->addExpression('AVG([tt2].[priority])');
// Create another query that adds a clause using the subqueries.
$select = $this->connection
->select('test', 't');
$select->addField('t', 'name');
$select->condition($subquery1, $subquery2, '>');
// The resulting query should be equivalent to:
// SELECT t.name
// FROM test t
// WHERE (SELECT AVG(tt.priority) FROM test_task tt WHERE tt.pid = t.id) > (SELECT AVG(tt2.priority) FROM test_task tt2)
$people = $select->execute()
->fetchCol();
$this->assertEqualsCanonicalizing([
'John',
], $people, 'Returned John.');
}
/**
* Tests that we can use multiple subqueries.
*
* This test uses a subquery at the left hand side and multiple subqueries at
* the right hand side. The test query may not be that logical but that's due
* to the limited amount of data and tables. 'Valid' use cases do exist :)
*/
public function testConditionSubquerySelect4() : void {
// Create subquery 1, which is just a normal query object.
$subquery1 = $this->connection
->select('test_task', 'tt');
$subquery1->addExpression('AVG([tt].[priority])');
$subquery1->where('[tt].[pid] = [t].[id]');
// Create subquery 2, which is just a normal query object.
$subquery2 = $this->connection
->select('test_task', 'tt2');
$subquery2->addExpression('MIN([tt2].[priority])');
$subquery2->where('[tt2].[pid] <> [t].[id]');
// Create subquery 3, which is just a normal query object.
$subquery3 = $this->connection
->select('test_task', 'tt3');
$subquery3->addExpression('AVG([tt3].[priority])');
$subquery3->where('[tt3].[pid] <> [t].[id]');
// Create another query that adds a clause using the subqueries.
$select = $this->connection
->select('test', 't');
$select->addField('t', 'name');
$select->condition($subquery1, [
$subquery2,
$subquery3,
], 'BETWEEN');
// The resulting query should be equivalent to:
// @code
// SELECT t.name AS name
// FROM {test} t
// WHERE (SELECT AVG(tt.priority) AS expression FROM {test_task} tt WHERE (tt.pid = t.id))
// BETWEEN (SELECT MIN(tt2.priority) AS expression FROM {test_task} tt2 WHERE (tt2.pid <> t.id))
// AND (SELECT AVG(tt3.priority) AS expression FROM {test_task} tt3 WHERE (tt3.pid <> t.id));
// @endcode
$people = $select->execute()
->fetchCol();
$this->assertEqualsCanonicalizing([
'George',
'Paul',
], $people, 'Returned George and Paul.');
}
/**
* Tests that we can use a subquery in a JOIN clause.
*/
public function testJoinSubquerySelect() : void {
// Create a subquery, which is just a normal query object.
$subquery = $this->connection
->select('test_task', 'tt');
$subquery->addField('tt', 'pid', 'pid');
$subquery->condition('priority', 1);
// Create another query that joins against the virtual table resulting
// from the subquery.
$select = $this->connection
->select('test', 't');
$select->join($subquery, 'tt', '[t].[id] = [tt].[pid]');
$select->addField('t', 'name');
// The resulting query should be equivalent to:
// @code
// SELECT t.name
// FROM test t
// INNER JOIN (SELECT tt.pid AS pid FROM test_task tt WHERE priority=1) tt ON t.id=tt.pid
// @endcode
$people = $select->execute()
->fetchCol();
$this->assertCount(2, $people, 'Returned the correct number of rows.');
}
/**
* Tests EXISTS subquery conditionals on SELECT statements.
*
* We essentially select all rows from the {test} table that have matching
* rows in the {test_people} table based on the shared name column.
*/
public function testExistsSubquerySelect() : void {
// Put George into {test_people}.
$this->connection
->insert('test_people')
->fields([
'name' => 'George',
'age' => 27,
'job' => 'Singer',
])
->execute();
// Base query to {test}.
$query = $this->connection
->select('test', 't')
->fields('t', [
'name',
]);
// Subquery to {test_people}.
$subquery = $this->connection
->select('test_people', 'tp')
->fields('tp', [
'name',
])
->where('[tp].[age] = [t].[age]');
$query->exists($subquery);
$result = $query->execute();
// Ensure that we got the right record.
$record = $result->fetch();
$this->assertEquals('George', $record->name, 'Fetched name is correct using EXISTS query.');
}
/**
* Tests NOT EXISTS subquery conditionals on SELECT statements.
*
* We essentially select all rows from the {test} table that don't have
* matching rows in the {test_people} table based on the shared name column.
*/
public function testNotExistsSubquerySelect() : void {
// Put George into {test_people}.
$this->connection
->insert('test_people')
->fields([
'name' => 'George',
'age' => 27,
'job' => 'Singer',
])
->execute();
// Base query to {test}.
$query = $this->connection
->select('test', 't')
->fields('t', [
'name',
]);
// Subquery to {test_people}.
$subquery = $this->connection
->select('test_people', 'tp')
->fields('tp', [
'name',
])
->where('[tp].[age] = [t].[age]');
$query->notExists($subquery);
// Ensure that we got the right number of records.
$people = $query->execute()
->fetchCol();
$this->assertCount(3, $people, 'NOT EXISTS query returned the correct results.');
}
}
Classes
Title | Deprecated | Summary |
---|---|---|
SelectSubqueryTest | Tests the Select query builder. |
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