diff --git a/application/displayblock.class.inc.php b/application/displayblock.class.inc.php
index ad3c75cc4..d03dfd291 100644
--- a/application/displayblock.class.inc.php
+++ b/application/displayblock.class.inc.php
@@ -1898,8 +1898,8 @@ class MenuBlock extends DisplayBlock
 			}
 
 			// Any style actions
-			// - Bulk actions on objects set (except unions...)
-			if ($iSetCount > 1 && !$this->GetFilter() instanceof DBUnionSearch) {
+			// - Bulk actions on objects set
+			if ($iSetCount > 1) {
 				// Bulk actions for each selected classes (eg. "link" and "remote" on n:n relations)
 				foreach ($aSelectedClasses as $sSelectedAlias => $sSelectedClass) {
 					$sSelectedClassName = MetaModel::GetName($sSelectedClass);
diff --git a/core/dbunionsearch.class.php b/core/dbunionsearch.class.php
index 454333c94..485162476 100644
--- a/core/dbunionsearch.class.php
+++ b/core/dbunionsearch.class.php
@@ -25,7 +25,7 @@ class DBUnionSearch extends DBSearch
 {
 	protected $aSearches; // source queries
 	protected $aSelectedClasses; // alias => classes (lowest common ancestors) computed at construction
-
+	protected $aColumnToAliases;
     /**
      * DBUnionSearch constructor.
      *
@@ -94,11 +94,14 @@ class DBUnionSearch extends DBSearch
 
 	/**
 	 * Find the lowest common ancestor for each of the selected class
+	 *
+	 * @throws \Exception
 	 */
 	protected function ComputeSelectedClasses()
 	{
 		// 1 - Collect all the column/classes
-		$aColumnToClasses = array();
+		$aColumnToClasses = [];
+		$this->aColumnToAliases = [];
 		foreach ($this->aSearches as $iPos => $oSearch)
 		{
 			$aSelected = array_values($oSearch->GetSelectedClasses());
@@ -117,7 +120,14 @@ class DBUnionSearch extends DBSearch
 
 			foreach ($aSelected as $iColumn => $sClass)
 			{
-				$aColumnToClasses[$iColumn][] = $sClass;
+				$aColumnToClasses[$iColumn][$iPos] = $sClass;
+			}
+
+			// Store the aliases by column to map them later (the first query impose the aliases)
+			$aAliases = array_keys($oSearch->GetSelectedClasses());
+			foreach ($aAliases as $iColumn => $sAlias)
+			{
+				$this->aColumnToAliases[$iColumn][$iPos] = $sAlias;
 			}
 		}
 
@@ -126,7 +136,7 @@ class DBUnionSearch extends DBSearch
 		$aColumnToAlias = array_keys($oFirstSearch->GetSelectedClasses());
 
 		// 3 - Compute alias => lowest common ancestor
-		$this->aSelectedClasses = array();
+		$this->aSelectedClasses = [];
 		foreach ($aColumnToClasses as $iColumn => $aClasses)
 		{
 			$sAlias = $aColumnToAlias[$iColumn];
@@ -215,15 +225,32 @@ class DBUnionSearch extends DBSearch
 
 	/**
 	 * @param array $aSelectedClasses array of aliases
-	 * @throws CoreException
+	 *
+	 * @throws \Exception
 	 */
 	public function SetSelectedClasses($aSelectedClasses)
 	{
+		// Get the columns corresponding the given aliases
+		$aSelectedColumns = [];
+		$oFirstSearch = $this->aSearches[0];
+		$aAliasesToColumn = array_flip(array_keys($oFirstSearch->GetSelectedClasses()));
+		foreach ($aSelectedClasses as $sSelectedAlias) {
+			if (!isset($aAliasesToColumn[$sSelectedAlias])) {
+				throw new CoreException("SetSelectedClasses: Invalid class alias $sSelectedAlias");
+			}
+			$aSelectedColumns[] = $aAliasesToColumn[$sSelectedAlias];
+		}
+
 		// 1 - change for each search
-		foreach ($this->aSearches as $oSearch)
+		foreach ($this->aSearches as $iPos => $oSearch)
 		{
+			$aCurrentSelectedAliases = [];
+			foreach ($aSelectedColumns as $iColumn) {
+				$aCurrentSelectedAliases[] = $this->aColumnToAliases[$iColumn][$iPos];
+			}
+
 			// Throws an exception if not valid
-			$oSearch->SetSelectedClasses($aSelectedClasses);
+			$oSearch->SetSelectedClasses($aCurrentSelectedAliases);
 		}
 		// 2 - update the lowest common ancestors
 		$this->ComputeSelectedClasses();
diff --git a/tests/php-unit-tests/unitary-tests/core/DBSearchIntersectTest.php b/tests/php-unit-tests/unitary-tests/core/DBSearchIntersectTest.php
index 5cb13ed19..b87c44de3 100644
--- a/tests/php-unit-tests/unitary-tests/core/DBSearchIntersectTest.php
+++ b/tests/php-unit-tests/unitary-tests/core/DBSearchIntersectTest.php
@@ -58,12 +58,11 @@ class DBSearchIntersectTest extends ItopTestCase
 			'alias' => "ApplicationSolution",
 			'result' => "SELECT `ApplicationSolution` FROM ApplicationSolution AS `ApplicationSolution` WHERE (`ApplicationSolution`.`org_id` = 3) UNION SELECT `BusinessProcess` FROM BusinessProcess AS `BusinessProcess` WHERE (`BusinessProcess`.`org_id` = 3)");
 
-// Bug to fix
-//		$aTests['Test union #2902'] = array(
-//			'left' => "SELECT `L-1` FROM ServiceFamily AS `L-1` WHERE 1",
-//			'right' => "SELECT `sf` FROM ServiceFamily AS `sf` JOIN Service AS `s` ON `s`.servicefamily_id = `sf`.id JOIN lnkCustomerContractToService AS `l1` ON `l1`.service_id = `s`.id JOIN CustomerContract AS `cc` ON `l1`.customercontract_id = `cc`.id WHERE (`cc`.`org_id` = 3) UNION SELECT `sf` FROM ServiceFamily AS `sf` JOIN Service AS `s` ON `s`.servicefamily_id = `sf`.id JOIN lnkCustomerContractToService AS `l1` ON `l1`.service_id = `s`.id JOIN CustomerContract AS `cc` ON `l1`.customercontract_id = `cc`.id JOIN Organization AS `child` ON `cc`.org_id = `child`.id JOIN Organization AS `root` ON `child`.parent_id BELOW `root`.id WHERE (`root`.`id` = 3)",
-//			'alias' => "L-1",
-//			'result' => "SELECT `L-1` FROM ServiceFamily AS `L-1` JOIN Service AS `s` ON `s`.servicefamily_id = `L-1`.id JOIN lnkCustomerContractToService AS `l1` ON `l1`.service_id = `s`.id JOIN CustomerContract AS `cc` ON `l1`.customercontract_id = `cc`.id WHERE (`cc`.`org_id` = 3) UNION SELECT `L-1` FROM ServiceFamily AS `L-1` JOIN Service AS `s` ON `s`.servicefamily_id = `L-1`.id JOIN lnkCustomerContractToService AS `l1` ON `l1`.service_id = `s`.id JOIN CustomerContract AS `cc` ON `l1`.customercontract_id = `cc`.id JOIN Organization AS `child` ON `cc`.org_id = `child`.id JOIN Organization AS `root` ON `child`.parent_id BELOW `root`.id WHERE (`root`.`id` = 3)");
+		$aTests['Test union #2902'] = array(
+			'left' => "SELECT `L-1` FROM ServiceFamily AS `L-1` WHERE 1",
+			'right' => "SELECT `sf` FROM ServiceFamily AS `sf` JOIN Service AS `s` ON `s`.servicefamily_id = `sf`.id JOIN lnkCustomerContractToService AS `l1` ON `l1`.service_id = `s`.id JOIN CustomerContract AS `cc` ON `l1`.customercontract_id = `cc`.id WHERE (`cc`.`org_id` = 3) UNION SELECT `sf` FROM ServiceFamily AS `sf` JOIN Service AS `s` ON `s`.servicefamily_id = `sf`.id JOIN lnkCustomerContractToService AS `l1` ON `l1`.service_id = `s`.id JOIN CustomerContract AS `cc` ON `l1`.customercontract_id = `cc`.id JOIN Organization AS `child` ON `cc`.org_id = `child`.id JOIN Organization AS `root` ON `child`.parent_id BELOW `root`.id WHERE (`root`.`id` = 3)",
+			'alias' => "L-1",
+			'result' => "SELECT `L-1` FROM ServiceFamily AS `L-1` JOIN Service AS `s` ON `s`.servicefamily_id = `L-1`.id JOIN lnkCustomerContractToService AS `l1` ON `l1`.service_id = `s`.id JOIN CustomerContract AS `cc` ON `l1`.customercontract_id = `cc`.id WHERE (`cc`.`org_id` = 3) UNION SELECT `L-1` FROM ServiceFamily AS `L-1` JOIN Service AS `s` ON `s`.servicefamily_id = `L-1`.id JOIN lnkCustomerContractToService AS `l1` ON `l1`.service_id = `s`.id JOIN CustomerContract AS `cc` ON `l1`.customercontract_id = `cc`.id JOIN Organization AS `child` ON `cc`.org_id = `child`.id JOIN Organization AS `root` ON `child`.parent_id BELOW `root`.id WHERE (`root`.`id` = 3)");
 
 		$aTests['Multiple selected classes inverted'] = array(
 			'left' => "SELECT `L`, `P` FROM Person AS `P` JOIN Location AS `L` ON `P`.location_id = `L`.id WHERE 1",
diff --git a/tests/php-unit-tests/unitary-tests/core/DBSearchTest.php b/tests/php-unit-tests/unitary-tests/core/DBSearchTest.php
index 954c87e71..1d11700f7 100644
--- a/tests/php-unit-tests/unitary-tests/core/DBSearchTest.php
+++ b/tests/php-unit-tests/unitary-tests/core/DBSearchTest.php
@@ -30,6 +30,7 @@ namespace Combodo\iTop\Test\UnitTest\Core;
 use CMDBSource;
 use Combodo\iTop\Test\UnitTest\ItopDataTestCase;
 use CoreOqlMultipleResultsForbiddenException;
+use DBObjectSet;
 use DBSearch;
 use Exception;
 use Expression;
@@ -745,4 +746,30 @@ class DBSearchTest extends ItopDataTestCase
 		$oSearch->MakeSelectQuery();
 		self::assertTrue(true);
 	}
+
+	/**
+	 * @dataProvider QueriesProvider
+	 * @param $sOQL
+	 *
+	 * @return void
+	 */
+	public function testQueries($sOQL)
+	{
+		$oSearch = DBSearch::FromOQL($sOQL);
+		$oSet = new DBObjectSet($oSearch);
+		if ($oSet->Count() > 0) {
+			$aSelectedAliases = array_keys($oSearch->GetSelectedClasses());
+			$aFirstRow = $oSet->FetchAssoc();
+			$aAliases = array_keys($aFirstRow);
+			$this->assertEquals($aSelectedAliases, $aAliases);
+		}
+	}
+
+	public function QueriesProvider()
+	{
+		return [
+			['SELECT L,P FROM Person AS P JOIN Location AS L ON P.location_id=L.id'],
+			['SELECT P,L FROM Person AS P JOIN Location AS L ON P.location_id=L.id'],
+		];
+	}
 }
diff --git a/tests/php-unit-tests/unitary-tests/core/DBUnionSearchTest.php b/tests/php-unit-tests/unitary-tests/core/DBUnionSearchTest.php
index 5a622bd25..73d29859b 100644
--- a/tests/php-unit-tests/unitary-tests/core/DBUnionSearchTest.php
+++ b/tests/php-unit-tests/unitary-tests/core/DBUnionSearchTest.php
@@ -15,6 +15,52 @@ use Combodo\iTop\Test\UnitTest\ItopDataTestCase;
 class DBUnionSearchTest extends ItopDataTestCase
 {
 
+	/**
+	 * @dataProvider UnionSearchProvider
+	 *
+	 * @param $sOQL
+	 *
+	 * @return void
+	 * @throws \CoreException
+	 * @throws \OQLException
+	 */
+	public function testUnionSearch($sOQL)
+	{
+		$oSearch = DBSearch::FromOQL($sOQL);
+
+		$oSet = new DBObjectSet($oSearch);
+		if ($oSet->Count() > 0) {
+			$aSelectedAliases = array_keys($oSearch->GetSelectedClasses());
+			$aFirstRow = $oSet->FetchAssoc();
+			$aAliases = array_keys($aFirstRow);
+			$this->assertEquals($aSelectedAliases, $aAliases);
+		}
+
+		$aSelectedClasses = $oSearch->GetSelectedClasses();
+		foreach ($aSelectedClasses as $sSelectedAlias => $sSelectedClass) {
+			$oSearchTest = $oSearch->DeepClone();
+			$oSearchTest->SetSelectedClasses([$sSelectedAlias]);
+			$oSet = new DBObjectSet($oSearchTest);
+			if ($oSet->Count() > 0) {
+				$aSelectedAliases = array_keys($oSearchTest->GetSelectedClasses());
+				$aFirstRow = $oSet->FetchAssoc();
+				$aAliases = array_keys($aFirstRow);
+				$this->assertEquals($aSelectedAliases, $aAliases);
+			}
+		}
+	}
+
+	public function UnionSearchProvider()
+	{
+		return [
+			'Same class' => ["SELECT Server UNION SELECT Server"],
+			'different class same alias' => ['SELECT Server AS fci UNION SELECT VirtualMachine AS fci'],
+			'different class no alias' => ['SELECT Server UNION SELECT VirtualMachine'],
+			'multiple classes same alias' => ['SELECT `L`, `P` FROM Location AS `L` JOIN Person AS `P` ON `P`.location_id = `L`.id WHERE (`L`.`org_id` = 3) UNION SELECT `L`, `P` FROM Location AS `L` JOIN Person AS `P` ON `P`.location_id = `L`.id WHERE (`L`.`org_id` = 2)'],
+			'multiple classes' => ['SELECT `L`, `P` FROM Location AS `L` JOIN Person AS `P` ON `P`.location_id = `L`.id WHERE (`L`.`org_id` = 3) UNION SELECT `L1`, `P1` FROM Person AS `P1` JOIN Location AS `L1` ON `P1`.location_id = `L1`.id WHERE (`P1`.`org_id` = 2)'],
+		];
+	}
+
 	public function testFilterOnFirstSelectedClass()
 	{
 		$sSourceOQL = 'SELECT `Person`, `Location` FROM Person AS `Person` JOIN Location AS `Location` ON `Person`.location_id = `Location`.id WHERE (`Location`.`id` = 1)';