diff -u b/core/lib/Drupal/Core/Database/Connection.php b/core/lib/Drupal/Core/Database/Connection.php
--- b/core/lib/Drupal/Core/Database/Connection.php
+++ b/core/lib/Drupal/Core/Database/Connection.php
@@ -781,7 +781,6 @@
     $this->expandArguments($query, $args);
     $stmt = $this->prepareStatement($query, $options);
 
-
     try {
       $stmt->execute($args, $options);
 
diff -u b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
--- b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
+++ b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
@@ -22,7 +22,7 @@
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
-// cspell:ignore destid idmap sourceid
+// cspell:ignore destid idmap sourceid psql
 
 /**
  * Defines the sql based ID map implementation.
@@ -298,22 +298,7 @@
    *   The fully qualified map table name.
    */
   public function getQualifiedMapTableName() {
-    $connection = $this->getDatabase();
-
-    switch ($connection->databaseType()) {
-      case 'psql':
-        // PostgreSQL doesn't support cross DB merges. So only use schema and
-        // prefixed table name.
-        $info => $connection->schema()->getPrefixInfo($this->mapTableName);
-        $qualifiedMapTableName = $info['schema'] . '.' . $info['table'];
-        break;
-
-      default:
-        $qualifiedMapTableName = $connection->getFullQualifiedTableName($this->mapTableName);
-        break;
-    }
-
-    return $qualifiedMapTableName;
+    return $this->getDatabase()->getFullQualifiedTableName($this->mapTableName);
   }
 
   /**
diff -u b/core/modules/pgsql/src/Driver/Database/pgsql/Connection.php b/core/modules/pgsql/src/Driver/Database/pgsql/Connection.php
--- b/core/modules/pgsql/src/Driver/Database/pgsql/Connection.php
+++ b/core/modules/pgsql/src/Driver/Database/pgsql/Connection.php
@@ -73,8 +73,8 @@
    * Constructs a connection object.
    */
   public function __construct(\PDO $connection, array $connection_options) {
-    // We need to set the connectionOptions before the parent,
-    // because setPrefix needs this.
+    // We need to set the connectionOptions before the parent, because setPrefix
+    // needs this.
     $this->connectionOptions = $connection_options;
 
     parent::__construct($connection, $connection_options);
@@ -314,11 +314,10 @@
    */
   public function getFullQualifiedTableName($table) {
     $options = $this->getConnectionOptions();
-    $info = $this->schema()->getPrefixInfo($table);
 
     // The fully qualified table name in PostgreSQL is in the form of
     // <database>.<schema>.<table>.
-    return $options['database'] . '.' . $info['schema'] . '.' . $info['table'];
+    return $options['database'] . '.' . $options['schema'] . '.' . $this->getPrefix() . $table;
   }
 
   /**
diff -u b/core/modules/pgsql/src/Driver/Database/pgsql/Schema.php b/core/modules/pgsql/src/Driver/Database/pgsql/Schema.php
--- b/core/modules/pgsql/src/Driver/Database/pgsql/Schema.php
+++ b/core/modules/pgsql/src/Driver/Database/pgsql/Schema.php
@@ -58,14 +58,9 @@
 
     $connectionInfo = $connection->getConnectionOptions();
 
-
+    // If the schema is not set in the connection options than schema defaults
+    // to public.
     $this->defaultSchema = $connectionInfo['schema'] ?? 'public';
-
-    // Set the default schema when it is not "public".
-    if (isset($connection_options['schema']) && ($connection_options['schema'] != 'public')) {
-      $this->connection->exec("SET SEARCH_PATH TO " . $connection_options['schema']);
-    }
-
   }
 
   /**
@@ -107,12 +102,12 @@
     }
 
     if (strlen($identifierName) > $this->maxIdentifierLength) {
-      $saveIdentifier = 'drupal_' . $this->hashBase64($identifierName) . '_' . $tag;
+      $saveIdentifier = '"drupal_' . $this->hashBase64($identifierName) . '_' . $tag . '"';
     }
     else {
       $saveIdentifier = $identifierName;
     }
-    return $this->connection->escapeTable($saveIdentifier);
+    return $saveIdentifier;
   }
 
   /**
@@ -155,7 +150,5 @@
       ];
       $this->connection->addSavepoint();
-
-
 
       try {
         // The bytea columns and sequences for a table can be found in
diff -u b/core/modules/pgsql/tests/src/Kernel/pgsql/NonPublicSchemaTest.php b/core/modules/pgsql/tests/src/Kernel/pgsql/NonPublicSchemaTest.php
--- b/core/modules/pgsql/tests/src/Kernel/pgsql/NonPublicSchemaTest.php
+++ b/core/modules/pgsql/tests/src/Kernel/pgsql/NonPublicSchemaTest.php
@@ -8,6 +8,8 @@
 use Drupal\KernelTests\Core\Database\DatabaseTestSchemaInstallTrait;
 use Drupal\KernelTests\Core\Database\DriverSpecificKernelTestBase;
 
+// cSpell:ignore nspname schemaname Upserting indexdef
+
 /**
  * Tests schema API for the PostgreSQL driver.
  *
@@ -39,7 +41,6 @@
 
     $this->connection = Database::getConnection('testing_fake', 'default');
 
-
     $table_specification = [
       'description' => 'Schema table description may contain "quotes" and could be long—very long indeed.',
       'fields' => [
@@ -79,8 +80,8 @@
     $this->connection->insert('faking_table')
       ->fields(
         [
-        'id' => '1',
-        'test_field' => '123',
+          'id' => '1',
+          'test_field' => '123',
         ]
       )->execute();
 
@@ -111,7 +112,7 @@
     $this->assertTrue($this->connection->schema()->tableExists('faking_table'));
 
     // Hardcoded assertion that we created the table in the non-public schema.
-    $this->assertCount(1,  $this->connection->query("SELECT * FROM pg_tables WHERE schemaname = 'testing_fake' AND tablename = :prefixedTable", [':prefixedTable' => $this->connection->getPrefix() . "faking_table"] )->fetchAll());
+    $this->assertCount(1, $this->connection->query("SELECT * FROM pg_tables WHERE schemaname = 'testing_fake' AND tablename = :prefixedTable", [':prefixedTable' => $this->connection->getPrefix() . "faking_table"])->fetchAll());
   }
 
   /**
@@ -145,7 +146,6 @@
         'test_field' => '55',
       ])->execute();
 
-
     // Testing that the insert is correct.
     $results = $this->connection->select('faking_table')->fields('faking_table')->condition('id', '123')->execute()->fetchAll();
     $this->assertIsArray($results);
@@ -234,7 +234,6 @@
     $this->assertSame('343', $merge_results[0]->test_field);
   }
 
-
   /**
    * @covers \Drupal\Core\Database\Driver\pgsql\Connection::delete
    * @covers \Drupal\Core\Database\Driver\pgsql\Connection::truncate
@@ -269,7 +268,7 @@
 
     $this->assertTrue($this->connection->schema()->indexExists('faking_table', 'test_field'));
 
-    $results = $this->connection->query("SELECT * FROM pg_indexes WHERE indexname = :indexname", [':indexname' => $this->connection->getPrefix() . 'faking_table__test_field__idx'] )->fetchAll();
+    $results = $this->connection->query("SELECT * FROM pg_indexes WHERE indexname = :indexname", [':indexname' => $this->connection->getPrefix() . 'faking_table__test_field__idx'])->fetchAll();
 
     $this->assertCount(1, $results);
     $this->assertSame('testing_fake', $results[0]->schemaname);
@@ -293,7 +292,7 @@
     // @todo remove comments when: https://www.drupal.org/project/drupal/issues/3325358 is committed.
     // $this->assertTrue($this->connection->schema()->indexExists('faking_table', 'test_field'));
 
-    $results = $this->connection->query("SELECT * FROM pg_indexes WHERE indexname = :indexname", [':indexname' => $this->connection->getPrefix() . 'faking_table__test_field__key'] )->fetchAll();
+    $results = $this->connection->query("SELECT * FROM pg_indexes WHERE indexname = :indexname", [':indexname' => $this->connection->getPrefix() . 'faking_table__test_field__key'])->fetchAll();
 
     // Check the unique key columns.
     $this->assertCount(1, $results);
@@ -301,7 +300,6 @@
     $this->assertSame($this->connection->getPrefix() . 'faking_table', $results[0]->tablename);
     $this->assertStringContainsString('USING btree (test_field)', $results[0]->indexdef);
 
-
     $this->connection->schema()->dropUniqueKey('faking_table', 'test_field');
 
     // This function will not work due to a the fact that indexExist() does not search for keys without idx tag.
@@ -362,2 +360,3 @@
   }
+
 }