diff --git a/UPGRADE.md b/UPGRADE.md
index ba0fbe9ef28..8aeafd0b717 100644
--- a/UPGRADE.md
+++ b/UPGRADE.md
@@ -8,6 +8,62 @@ awareness about deprecated code.
 
 # Upgrade to 4.0
 
+## BC BREAK: Removed `AbstractSchemaManager::getSchemaSearchPaths()`.
+
+The `AbstractSchemaManager::getSchemaSearchPaths()` method has been removed.
+
+The schema configuration returned by `AbstractSchemaManager::createSchemaConfig()` will contain a non-empty schema name
+only for those database platforms that support schemas (currently, PostgreSQL).
+
+The schema returned by `AbstractSchemaManager::createSchema()` will have a non-empty name only for those
+database platforms that support schemas.
+
+## BC BREAK: Removed `AbstractAsset::getFullQualifiedName()`.
+
+The `AbstractAsset::getFullQualifiedName()` method has been removed.
+
+## BC BREAK: Removed schema methods related to explicit foreign key indexes.
+
+The following methods have been removed:
+
+- `Schema::hasExplicitForeignKeyIndexes()`,
+- `SchemaConfig::hasExplicitForeignKeyIndexes()`,
+- `SchemaConfig::setExplicitForeignKeyIndexes()`.
+
+## BC BREAK: Removed `Schema::getTableNames()`.
+
+The `Schema::getTableNames()` method has been removed.
+
+## BC BREAK: Changes in `Schema` method return values.
+
+The `Schema::getNamespaces()`, `Schema::getTables()` and `Schema::getSequences()` methods will return numeric arrays
+of namespaces, tables and sequences respectively instead of associative arrays.
+
+## BC BREAK: Removed `SqlitePlatform::udf*()` methods.
+
+The following `SqlitePlatform` methods have been removed:
+
+- `udfSqrt()`,
+- `udfMod()`,
+- `udfLocate()`.
+
+## BC BREAK: `SQLServerPlatform` methods marked protected.
+
+The following `SQLServerPlatform` methods have been marked protected:
+
+- `getDefaultConstraintDeclarationSQL()`,
+- `getAddExtendedPropertySQL()`,
+- `getDropExtendedPropertySQL()`,
+- `getUpdateExtendedPropertySQL()`.
+
+## BC BREAK: `OraclePlatform` methods marked protected.
+
+The `OraclePlatform::getCreateAutoincrementSql()` method has been marked protected.
+
+## BC BREAK: Removed `OraclePlatform::assertValidIdentifier()`.
+
+The `OraclePlatform::assertValidIdentifier()` method has been removed.
+
 ## BC BREAK: Changed signatures of `AbstractPlatform::getIndexDeclarationSQL()` and `::getUniqueConstraintDeclarationSQL()`
 
 The `AbstractPlatform::getIndexDeclarationSQL()` and `::getUniqueConstraintDeclarationSQL()` methods no longer accept
diff --git a/phpcs.xml.dist b/phpcs.xml.dist
index b181bb0bb66..d641f680e81 100644
--- a/phpcs.xml.dist
+++ b/phpcs.xml.dist
@@ -23,7 +23,6 @@
         <exclude name="SlevomatCodingStandard.Classes.SuperfluousExceptionNaming"/>
         <exclude name="SlevomatCodingStandard.Classes.DisallowLateStaticBindingForConstants.DisallowedLateStaticBindingForConstant"/>
         <exclude name="SlevomatCodingStandard.ControlStructures.ControlStructureSpacing.IncorrectLinesCountAfterLastControlStructure"/>
-        <exclude name="SlevomatCodingStandard.ControlStructures.RequireNullCoalesceEqualOperator.RequiredNullCoalesceEqualOperator"/>
 
         <exclude name="PSR2.Methods.MethodDeclaration.Underscore"/>
         <!-- https://github.com/slevomat/coding-standard/issues/867 -->
diff --git a/psalm.xml.dist b/psalm.xml.dist
index 89251873f90..1f658d5f81e 100644
--- a/psalm.xml.dist
+++ b/psalm.xml.dist
@@ -64,37 +64,8 @@
                     TODO: remove in 4.0.0
                 -->
                 <referencedMethod name="Doctrine\DBAL\Schema\Schema::getMigrateToSql"/>
-                <!--
-                    TODO: remove in 4.0.0
-                -->
-                <referencedMethod name="Doctrine\DBAL\Platforms\OraclePlatform::assertValidIdentifier"/>
-                <!--
-                    TODO: remove in 4.0.0
-                    See https://github.com/doctrine/dbal/pull/4822
-                -->
-                <referencedMethod name="Doctrine\DBAL\Schema\SchemaConfig::hasExplicitForeignKeyIndexes"/>
-                <!--
-                    TODO: remove in 4.0.0
-                    See https://github.com/doctrine/dbal/pull/4814
-                -->
-                <referencedMethod name="Doctrine\DBAL\Schema\AbstractAsset::getFullQualifiedName"/>
-                <!--
-                    TODO: remove in 4.0.0
-                    See https://github.com/doctrine/dbal/pull/4821
-                -->
-                <referencedMethod name="Doctrine\DBAL\Schema\AbstractSchemaManager::getSchemaSearchPaths"/>
-                <referencedMethod name="Doctrine\DBAL\Schema\PostgreSQLSchemaManager::getSchemaSearchPaths"/>
             </errorLevel>
         </DeprecatedMethod>
-        <DeprecatedProperty>
-            <errorLevel type="suppress">
-                <!--
-                    This suppression should be removed in 4.0.x
-                    See https://github.com/doctrine/dbal/pull/4822
-                -->
-                <referencedProperty name="Doctrine\DBAL\Schema\SchemaConfig::$hasExplicitForeignKeyIndexes"/>
-            </errorLevel>
-        </DeprecatedProperty>
         <DocblockTypeContradiction>
             <errorLevel type="suppress">
                 <!--
diff --git a/src/Connections/PrimaryReadReplicaConnection.php b/src/Connections/PrimaryReadReplicaConnection.php
index e316bf9d99d..4daa184f799 100644
--- a/src/Connections/PrimaryReadReplicaConnection.php
+++ b/src/Connections/PrimaryReadReplicaConnection.php
@@ -152,7 +152,7 @@ public function connect(?string $connectionName = null): void
     protected function performConnect(?string $connectionName = null): void
     {
         $requestedConnectionChange = ($connectionName !== null);
-        $connectionName            = $connectionName ?? 'replica';
+        $connectionName          ??= 'replica';
 
         if ($connectionName !== 'replica' && $connectionName !== 'primary') {
             throw new InvalidArgumentException('Invalid option to connect(), only primary or replica allowed.');
diff --git a/src/Driver/PDO/SQLite/Driver.php b/src/Driver/PDO/SQLite/Driver.php
index 8c7aa3421ee..474aa12055c 100644
--- a/src/Driver/PDO/SQLite/Driver.php
+++ b/src/Driver/PDO/SQLite/Driver.php
@@ -5,9 +5,9 @@
 namespace Doctrine\DBAL\Driver\PDO\SQLite;
 
 use Doctrine\DBAL\Driver\AbstractSQLiteDriver;
+use Doctrine\DBAL\Driver\API\SQLite\UserDefinedFunctions;
 use Doctrine\DBAL\Driver\Connection as ConnectionInterface;
 use Doctrine\DBAL\Driver\PDO\Connection;
-use Doctrine\DBAL\Platforms\SqlitePlatform;
 
 use function array_merge;
 
@@ -15,9 +15,18 @@ final class Driver extends AbstractSQLiteDriver
 {
     /** @var mixed[] */
     private array $userDefinedFunctions = [
-        'sqrt' => ['callback' => [SqlitePlatform::class, 'udfSqrt'], 'numArgs' => 1],
-        'mod'  => ['callback' => [SqlitePlatform::class, 'udfMod'], 'numArgs' => 2],
-        'locate'  => ['callback' => [SqlitePlatform::class, 'udfLocate'], 'numArgs' => -1],
+        'sqrt' => [
+            'callback' => 'sqrt',
+            'numArgs' => 1,
+        ],
+        'mod' => [
+            'callback' => [UserDefinedFunctions::class, 'mod'],
+            'numArgs' => 2,
+        ],
+        'locate' => [
+            'callback' => [UserDefinedFunctions::class, 'locate'],
+            'numArgs' => -1,
+        ],
     ];
 
     /**
diff --git a/src/Platforms/OraclePlatform.php b/src/Platforms/OraclePlatform.php
index acb91362698..5c5b71c419f 100644
--- a/src/Platforms/OraclePlatform.php
+++ b/src/Platforms/OraclePlatform.php
@@ -4,7 +4,6 @@
 
 namespace Doctrine\DBAL\Platforms;
 
-use Doctrine\DBAL\Exception;
 use Doctrine\DBAL\Exception\ColumnLengthRequired;
 use Doctrine\DBAL\Platforms\Keywords\KeywordList;
 use Doctrine\DBAL\Platforms\Keywords\OracleKeywords;
@@ -33,22 +32,6 @@
  */
 class OraclePlatform extends AbstractPlatform
 {
-    /**
-     * Assertion for Oracle identifiers.
-     *
-     * @deprecated
-     *
-     * @link http://docs.oracle.com/cd/B19306_01/server.102/b14200/sql_elements008.htm
-     *
-     * @throws Exception
-     */
-    public static function assertValidIdentifier(string $identifier): void
-    {
-        if (preg_match('(^(([a-zA-Z]{1}[a-zA-Z0-9_$#]{0,})|("[^"]+"))$)', $identifier) === 0) {
-            throw new Exception('Invalid Oracle identifier.');
-        }
-    }
-
     public function getSubstringExpression(string $string, string $start, ?string $length = null): string
     {
         if ($length === null) {
@@ -405,11 +388,9 @@ public function getListViewsSQL(string $database): string
     }
 
     /**
-     * @internal The method should be only used from within the OraclePlatform class hierarchy.
-     *
      * @return array<int, string>
      */
-    public function getCreateAutoincrementSql(string $name, string $table, int $start = 1): array
+    protected function getCreateAutoincrementSql(string $name, string $table, int $start = 1): array
     {
         $tableIdentifier   = $this->normalizeIdentifier($table);
         $quotedTableName   = $tableIdentifier->getQuotedName($this);
diff --git a/src/Platforms/SQLServerPlatform.php b/src/Platforms/SQLServerPlatform.php
index 8f2211a3e8a..25f56fe0945 100644
--- a/src/Platforms/SQLServerPlatform.php
+++ b/src/Platforms/SQLServerPlatform.php
@@ -307,14 +307,12 @@ protected function getCreateColumnCommentSQL(string $tableName, string $columnNa
     /**
      * Returns the SQL snippet for declaring a default constraint.
      *
-     * @internal The method should be only used from within the SQLServerPlatform class hierarchy.
-     *
      * @param string  $table  Name of the table to return the default constraint declaration for.
      * @param mixed[] $column Column definition.
      *
      * @throws InvalidArgumentException
      */
-    public function getDefaultConstraintDeclarationSQL(string $table, array $column): string
+    protected function getDefaultConstraintDeclarationSQL(string $table, array $column): string
     {
         if (! isset($column['default'])) {
             throw new InvalidArgumentException('Incomplete column definition. "default" required.');
@@ -678,8 +676,6 @@ protected function getRenameIndexSQL(string $oldIndexName, Index $index, string
     /**
      * Returns the SQL statement for adding an extended property to a database object.
      *
-     * @internal The method should be only used from within the SQLServerPlatform class hierarchy.
-     *
      * @link http://msdn.microsoft.com/en-us/library/ms180047%28v=sql.90%29.aspx
      *
      * @param string      $name       The name of the property to add.
@@ -691,7 +687,7 @@ protected function getRenameIndexSQL(string $oldIndexName, Index $index, string
      * @param string|null $level2Type The type of the object at level 2 the property belongs to.
      * @param string|null $level2Name The name of the object at level 2 the property belongs to.
      */
-    public function getAddExtendedPropertySQL(
+    protected function getAddExtendedPropertySQL(
         string $name,
         ?string $value = null,
         ?string $level0Type = null,
@@ -711,8 +707,6 @@ public function getAddExtendedPropertySQL(
     /**
      * Returns the SQL statement for dropping an extended property from a database object.
      *
-     * @internal The method should be only used from within the SQLServerPlatform class hierarchy.
-     *
      * @link http://technet.microsoft.com/en-gb/library/ms178595%28v=sql.90%29.aspx
      *
      * @param string      $name       The name of the property to drop.
@@ -723,7 +717,7 @@ public function getAddExtendedPropertySQL(
      * @param string|null $level2Type The type of the object at level 2 the property belongs to.
      * @param string|null $level2Name The name of the object at level 2 the property belongs to.
      */
-    public function getDropExtendedPropertySQL(
+    protected function getDropExtendedPropertySQL(
         string $name,
         ?string $level0Type = null,
         ?string $level0Name = null,
@@ -742,8 +736,6 @@ public function getDropExtendedPropertySQL(
     /**
      * Returns the SQL statement for updating an extended property of a database object.
      *
-     * @internal The method should be only used from within the SQLServerPlatform class hierarchy.
-     *
      * @link http://msdn.microsoft.com/en-us/library/ms186885%28v=sql.90%29.aspx
      *
      * @param string      $name       The name of the property to update.
@@ -755,7 +747,7 @@ public function getDropExtendedPropertySQL(
      * @param string|null $level2Type The type of the object at level 2 the property belongs to.
      * @param string|null $level2Name The name of the object at level 2 the property belongs to.
      */
-    public function getUpdateExtendedPropertySQL(
+    protected function getUpdateExtendedPropertySQL(
         string $name,
         ?string $value = null,
         ?string $level0Type = null,
diff --git a/src/Platforms/SqlitePlatform.php b/src/Platforms/SqlitePlatform.php
index 4263982a084..91ec7e5e8aa 100644
--- a/src/Platforms/SqlitePlatform.php
+++ b/src/Platforms/SqlitePlatform.php
@@ -4,7 +4,6 @@
 
 namespace Doctrine\DBAL\Platforms;
 
-use Doctrine\DBAL\Driver\API\SQLite\UserDefinedFunctions;
 use Doctrine\DBAL\Exception;
 use Doctrine\DBAL\Platforms\Keywords\KeywordList;
 use Doctrine\DBAL\Platforms\Keywords\SQLiteKeywords;
@@ -28,7 +27,6 @@
 use function array_values;
 use function implode;
 use function sprintf;
-use function sqrt;
 use function str_replace;
 use function strtolower;
 use function trim;
@@ -462,36 +460,6 @@ public function getTruncateTableSQL(string $tableName, bool $cascade = false): s
         return 'DELETE FROM ' . $tableIdentifier->getQuotedName($this);
     }
 
-    /**
-     * User-defined function for Sqlite that is used with PDO::sqliteCreateFunction().
-     *
-     * @deprecated The driver will use {@link sqrt()} in the next major release.
-     *
-     * @param int|float $value
-     */
-    public static function udfSqrt($value): float
-    {
-        return sqrt($value);
-    }
-
-    /**
-     * User-defined function for Sqlite that implements MOD(a, b).
-     *
-     * @deprecated The driver will use {@link UserDefinedFunctions::mod()} in the next major release.
-     */
-    public static function udfMod(int $a, int $b): int
-    {
-        return UserDefinedFunctions::mod($a, $b);
-    }
-
-    /**
-     * @deprecated The driver will use {@link UserDefinedFunctions::locate()} in the next major release.
-     */
-    public static function udfLocate(string $str, string $substr, int $offset = 0): int
-    {
-        return UserDefinedFunctions::locate($str, $substr, $offset);
-    }
-
     public function getForUpdateSQL(): string
     {
         return '';
diff --git a/src/Schema/AbstractAsset.php b/src/Schema/AbstractAsset.php
index e9172441251..dca2d597a2e 100644
--- a/src/Schema/AbstractAsset.php
+++ b/src/Schema/AbstractAsset.php
@@ -5,7 +5,6 @@
 namespace Doctrine\DBAL\Schema;
 
 use Doctrine\DBAL\Platforms\AbstractPlatform;
-use Doctrine\Deprecations\Deprecation;
 
 use function array_map;
 use function crc32;
@@ -86,34 +85,6 @@ public function getShortestName(?string $defaultNamespaceName): string
         return strtolower($shortestName);
     }
 
-    /**
-     * The normalized name is full-qualified and lower-cased. Lower-casing is
-     * actually wrong, but we have to do it to keep our sanity. If you are
-     * using database objects that only differentiate in the casing (FOO vs
-     * Foo) then you will NOT be able to use Doctrine Schema abstraction.
-     *
-     * Every non-namespaced element is prefixed with the default namespace
-     * name which is passed as argument to this method.
-     *
-     * @deprecated Use {@link getNamespaceName()} and {@link getName()} instead.
-     */
-    public function getFullQualifiedName(string $defaultNamespaceName): string
-    {
-        Deprecation::triggerIfCalledFromOutside(
-            'doctrine/dbal',
-            'https://github.com/doctrine/dbal/pull/4814',
-            'AbstractAsset::getFullQualifiedName() is deprecated.'
-            . ' Use AbstractAsset::getNamespaceName() and ::getName() instead.'
-        );
-
-        $name = $this->getName();
-        if ($this->_namespace === null) {
-            $name = $defaultNamespaceName . '.' . $name;
-        }
-
-        return strtolower($name);
-    }
-
     /**
      * Checks if this asset's name is quoted.
      */
diff --git a/src/Schema/AbstractSchemaManager.php b/src/Schema/AbstractSchemaManager.php
index fed4c1a9ef0..0e2e718f30d 100644
--- a/src/Schema/AbstractSchemaManager.php
+++ b/src/Schema/AbstractSchemaManager.php
@@ -12,7 +12,6 @@
 use Doctrine\DBAL\Exception\DatabaseRequired;
 use Doctrine\DBAL\Platforms\AbstractPlatform;
 use Doctrine\DBAL\Platforms\Exception\NotSupported;
-use Doctrine\Deprecations\Deprecation;
 use Throwable;
 
 use function array_filter;
@@ -944,11 +943,6 @@ public function createSchemaConfig(): SchemaConfig
         $schemaConfig = new SchemaConfig();
         $schemaConfig->setMaxIdentifierLength($this->_platform->getMaxIdentifierLength());
 
-        $searchPaths = $this->getSchemaSearchPaths();
-        if (isset($searchPaths[0])) {
-            $schemaConfig->setName($searchPaths[0]);
-        }
-
         $params = $this->_conn->getParams();
         if (! isset($params['defaultTableOptions'])) {
             $params['defaultTableOptions'] = [];
@@ -963,39 +957,6 @@ public function createSchemaConfig(): SchemaConfig
         return $schemaConfig;
     }
 
-    /**
-     * The search path for namespaces in the currently connected database.
-     *
-     * The first entry is usually the default namespace in the Schema. All
-     * further namespaces contain tables/sequences which can also be addressed
-     * with a short, not full-qualified name.
-     *
-     * For databases that don't support subschema/namespaces this method
-     * returns the name of the currently connected database.
-     *
-     * @deprecated
-     *
-     * @return array<int, string>
-     *
-     * @throws Exception
-     */
-    public function getSchemaSearchPaths(): array
-    {
-        Deprecation::triggerIfCalledFromOutside(
-            'doctrine/dbal',
-            'https://github.com/doctrine/dbal/pull/4821',
-            'AbstractSchemaManager::getSchemaSearchPaths() is deprecated.'
-        );
-
-        $database = $this->_conn->getDatabase();
-
-        if ($database !== null) {
-            return [$database];
-        }
-
-        return [];
-    }
-
     /**
      * Given a table comment this method tries to extract a type hint for Doctrine Type. If the type hint is found,
      * it's removed from the comment.
diff --git a/src/Schema/PostgreSQLSchemaManager.php b/src/Schema/PostgreSQLSchemaManager.php
index 05a228ebfe3..6014a56911e 100644
--- a/src/Schema/PostgreSQLSchemaManager.php
+++ b/src/Schema/PostgreSQLSchemaManager.php
@@ -8,13 +8,10 @@
 use Doctrine\DBAL\Platforms\PostgreSQLPlatform;
 use Doctrine\DBAL\Types\Type;
 use Doctrine\DBAL\Types\Types;
-use Doctrine\Deprecations\Deprecation;
 
 use function array_change_key_case;
-use function array_filter;
 use function array_keys;
 use function array_map;
-use function array_shift;
 use function assert;
 use function explode;
 use function implode;
@@ -36,8 +33,7 @@
  */
 class PostgreSQLSchemaManager extends AbstractSchemaManager
 {
-    /** @var array<int, string>|null */
-    private ?array $existingSchemaPaths = null;
+    private ?string $currentSchema = null;
 
     /**
      * {@inheritDoc}
@@ -54,47 +50,13 @@ public function listSchemaNames(): array
         );
     }
 
-    /**
-     * {@inheritDoc}
-     *
-     * @deprecated
-     */
-    public function getSchemaSearchPaths(): array
+    public function createSchemaConfig(): SchemaConfig
     {
-        Deprecation::triggerIfCalledFromOutside(
-            'doctrine/dbal',
-            'https://github.com/doctrine/dbal/pull/4821',
-            'PostgreSQLSchemaManager::getSchemaSearchPaths() is deprecated.'
-        );
-
-        $params = $this->_conn->getParams();
+        $config = parent::createSchemaConfig();
 
-        $searchPaths = $this->_conn->fetchOne('SHOW search_path');
-        assert($searchPaths !== false);
+        $config->setName($this->getCurrentSchema());
 
-        $schema = explode(',', $searchPaths);
-
-        if (isset($params['user'])) {
-            $schema = str_replace('"$user"', $params['user'], $schema);
-        }
-
-        return array_map('trim', $schema);
-    }
-
-    /**
-     * Gets names of all existing schemas in the current user's search path.
-     *
-     * @return array<int, string>
-     *
-     * @throws Exception
-     */
-    final protected function getExistingSchemaSearchPaths(): array
-    {
-        if ($this->existingSchemaPaths === null) {
-            $this->existingSchemaPaths = $this->determineExistingSchemaSearchPaths();
-        }
-
-        return $this->existingSchemaPaths;
+        return $config;
     }
 
     /**
@@ -104,26 +66,20 @@ final protected function getExistingSchemaSearchPaths(): array
      */
     protected function getCurrentSchema(): ?string
     {
-        $schemas = $this->getExistingSchemaSearchPaths();
-
-        return array_shift($schemas);
+        return $this->currentSchema ??= $this->determineCurrentSchema();
     }
 
     /**
-     * Determines the names of all existing schemas in the current user's search path.
-     *
-     * @return array<int,string>
+     * Determines the name of the current schema.
      *
      * @throws Exception
      */
-    protected function determineExistingSchemaSearchPaths(): array
+    protected function determineCurrentSchema(): string
     {
-        $names = $this->listSchemaNames();
-        $paths = $this->getSchemaSearchPaths();
+        $currentSchema = $this->_conn->fetchOne('SELECT current_schema()');
+        assert(is_string($currentSchema));
 
-        return array_filter($paths, static function ($v) use ($names): bool {
-            return in_array($v, $names, true);
-        });
+        return $currentSchema;
     }
 
     /**
diff --git a/src/Schema/Schema.php b/src/Schema/Schema.php
index 53812f37b17..80be94ab9aa 100644
--- a/src/Schema/Schema.php
+++ b/src/Schema/Schema.php
@@ -14,9 +14,8 @@
 use Doctrine\DBAL\Schema\Visitor\DropSchemaSqlCollector;
 use Doctrine\DBAL\Schema\Visitor\NamespaceVisitor;
 use Doctrine\DBAL\Schema\Visitor\Visitor;
-use Doctrine\Deprecations\Deprecation;
 
-use function array_keys;
+use function array_values;
 use function strpos;
 use function strtolower;
 
@@ -79,7 +78,12 @@ public function __construct(
         }
 
         $this->_schemaConfig = $schemaConfig;
-        $this->_setName($schemaConfig->getName() ?? 'public');
+
+        $name = $schemaConfig->getName();
+
+        if ($name !== null) {
+            $this->_setName($name);
+        }
 
         foreach ($namespaces as $namespace) {
             $this->createNamespace($namespace);
@@ -94,20 +98,6 @@ public function __construct(
         }
     }
 
-    /**
-     * @deprecated
-     */
-    public function hasExplicitForeignKeyIndexes(): bool
-    {
-        Deprecation::trigger(
-            'doctrine/dbal',
-            'https://github.com/doctrine/dbal/pull/4822',
-            'Schema::hasExplicitForeignKeyIndexes() is deprecated.'
-        );
-
-        return $this->_schemaConfig->hasExplicitForeignKeyIndexes();
-    }
-
     /**
      * @throws SchemaException
      */
@@ -158,21 +148,21 @@ protected function _addSequence(Sequence $sequence): void
     /**
      * Returns the namespaces of this schema.
      *
-     * @return array<string, string> A list of namespace names.
+     * @return list<string> A list of namespace names.
      */
     public function getNamespaces(): array
     {
-        return $this->namespaces;
+        return array_values($this->namespaces);
     }
 
     /**
      * Gets all tables of this schema.
      *
-     * @return array<string, Table>
+     * @return list<Table>
      */
     public function getTables(): array
     {
-        return $this->_tables;
+        return array_values($this->_tables);
     }
 
     /**
@@ -199,9 +189,23 @@ private function getFullQualifiedAssetName(string $name): string
         return strtolower($name);
     }
 
+    /**
+     * The normalized name is qualified and lower-cased. Lower-casing is
+     * actually wrong, but we have to do it to keep our sanity. If you are
+     * using database objects that only differentiate in the casing (FOO vs
+     * Foo) then you will NOT be able to use Doctrine Schema abstraction.
+     *
+     * Every non-namespaced element is prefixed with this schema name.
+     */
     private function normalizeName(AbstractAsset $asset): string
     {
-        return $asset->getFullQualifiedName($this->getName());
+        $name = $asset->getName();
+
+        if ($asset->getNamespaceName() === null) {
+            $name = $this->getName() . '.' . $name;
+        }
+
+        return strtolower($name);
     }
 
     /**
@@ -236,26 +240,6 @@ public function hasTable(string $name): bool
         return isset($this->_tables[$name]);
     }
 
-    /**
-     * Gets all table names, prefixed with a schema name, even the default one if present.
-     *
-     * @deprecated Use {@link getTables()} and {@link Table::getName()} instead.
-     *
-     * @return array<int, string>
-     */
-    public function getTableNames(): array
-    {
-        Deprecation::trigger(
-            'doctrine/dbal',
-            'https://github.com/doctrine/dbal/pull/4800',
-            'Schema::getTableNames() is deprecated.'
-            . ' Use Schema::getTables() and Table::getName() instead.',
-            __METHOD__
-        );
-
-        return array_keys($this->_tables);
-    }
-
     public function hasSequence(string $name): bool
     {
         $name = $this->getFullQualifiedAssetName($name);
@@ -277,11 +261,11 @@ public function getSequence(string $name): Sequence
     }
 
     /**
-     * @return array<string, Sequence>
+     * @return list<Sequence>
      */
     public function getSequences(): array
     {
-        return $this->_sequences;
+        return array_values($this->_sequences);
     }
 
     /**
diff --git a/src/Schema/SchemaConfig.php b/src/Schema/SchemaConfig.php
index 69b410d8bac..1e19f8d02d4 100644
--- a/src/Schema/SchemaConfig.php
+++ b/src/Schema/SchemaConfig.php
@@ -4,16 +4,11 @@
 
 namespace Doctrine\DBAL\Schema;
 
-use Doctrine\Deprecations\Deprecation;
-
 /**
  * Configuration for a Schema.
  */
 class SchemaConfig
 {
-    /** @deprecated */
-    protected bool $hasExplicitForeignKeyIndexes = false;
-
     protected int $maxIdentifierLength = 63;
 
     protected ?string $name = null;
@@ -21,34 +16,6 @@ class SchemaConfig
     /** @var array<string, mixed> */
     protected array $defaultTableOptions = [];
 
-    /**
-     * @deprecated
-     */
-    public function hasExplicitForeignKeyIndexes(): bool
-    {
-        Deprecation::triggerIfCalledFromOutside(
-            'doctrine/dbal',
-            'https://github.com/doctrine/dbal/pull/4822',
-            'SchemaConfig::hasExplicitForeignKeyIndexes() is deprecated.'
-        );
-
-        return $this->hasExplicitForeignKeyIndexes;
-    }
-
-    /**
-     * @deprecated
-     */
-    public function setExplicitForeignKeyIndexes(bool $flag): void
-    {
-        Deprecation::trigger(
-            'doctrine/dbal',
-            'https://github.com/doctrine/dbal/pull/4822',
-            'SchemaConfig::setExplicitForeignKeyIndexes() is deprecated.'
-        );
-
-        $this->hasExplicitForeignKeyIndexes = $flag;
-    }
-
     public function setMaxIdentifierLength(int $length): void
     {
         $this->maxIdentifierLength = $length;
@@ -70,7 +37,7 @@ public function getName(): ?string
     /**
      * Sets the default namespace name of schema objects.
      */
-    public function setName(string $name): void
+    public function setName(?string $name): void
     {
         $this->name = $name;
     }
diff --git a/src/Schema/SqliteSchemaManager.php b/src/Schema/SqliteSchemaManager.php
index d8d83fca844..97f90499d02 100644
--- a/src/Schema/SqliteSchemaManager.php
+++ b/src/Schema/SqliteSchemaManager.php
@@ -11,7 +11,6 @@
 use Doctrine\DBAL\Types\StringType;
 use Doctrine\DBAL\Types\TextType;
 use Doctrine\DBAL\Types\Type;
-use Doctrine\Deprecations\Deprecation;
 
 use function array_change_key_case;
 use function array_merge;
@@ -537,21 +536,4 @@ public function createComparator(): Comparator
     {
         return new SQLite\Comparator($this->getDatabasePlatform());
     }
-
-    /**
-     * {@inheritDoc}
-     *
-     * @deprecated
-     */
-    public function getSchemaSearchPaths(): array
-    {
-        Deprecation::triggerIfCalledFromOutside(
-            'doctrine/dbal',
-            'https://github.com/doctrine/dbal/pull/4821',
-            'SqliteSchemaManager::getSchemaSearchPaths() is deprecated.'
-        );
-
-        // SQLite does not support schemas or databases
-        return [];
-    }
 }
diff --git a/tests/Functional/Schema/PostgreSQLSchemaManagerTest.php b/tests/Functional/Schema/PostgreSQLSchemaManagerTest.php
index a5e291a247f..3be67c0ca1c 100644
--- a/tests/Functional/Schema/PostgreSQLSchemaManagerTest.php
+++ b/tests/Functional/Schema/PostgreSQLSchemaManagerTest.php
@@ -16,7 +16,6 @@
 
 use function array_map;
 use function array_pop;
-use function array_unshift;
 use function count;
 use function preg_match;
 use function strtolower;
@@ -28,19 +27,6 @@ protected function supportsPlatform(AbstractPlatform $platform): bool
         return $platform instanceof PostgreSQLPlatform;
     }
 
-    public function testGetSearchPath(): void
-    {
-        $expected = ['public'];
-
-        $params = $this->connection->getParams();
-
-        if (isset($params['user'])) {
-            array_unshift($expected, $params['user']);
-        }
-
-        self::assertEquals($expected, $this->schemaManager->getSchemaSearchPaths());
-    }
-
     public function testGetSchemaNames(): void
     {
         $names = $this->schemaManager->listSchemaNames();
diff --git a/tests/Functional/Schema/SchemaTest.php b/tests/Functional/Schema/SchemaTest.php
deleted file mode 100644
index c4241268f45..00000000000
--- a/tests/Functional/Schema/SchemaTest.php
+++ /dev/null
@@ -1,17 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Doctrine\DBAL\Tests\Functional\Schema;
-
-use Doctrine\DBAL\Schema\Schema;
-use Doctrine\DBAL\Tests\FunctionalTestCase;
-
-class SchemaTest extends FunctionalTestCase
-{
-    public function testSchemaName(): void
-    {
-        $schema = new Schema([], [], $this->connection->createSchemaManager()->createSchemaConfig());
-        self::assertNotEmpty($schema->getName());
-    }
-}
diff --git a/tests/Platforms/AbstractSQLServerPlatformTestCase.php b/tests/Platforms/AbstractSQLServerPlatformTestCase.php
index 44622b0d0c8..a451b3fa12d 100644
--- a/tests/Platforms/AbstractSQLServerPlatformTestCase.php
+++ b/tests/Platforms/AbstractSQLServerPlatformTestCase.php
@@ -1218,64 +1218,6 @@ protected function getQuotedAlterTableRenameIndexInSchemaSQL(): array
         ];
     }
 
-    /**
-     * @param mixed[] $column
-     *
-     * @dataProvider getGeneratesIdentifierNamesInDefaultConstraintDeclarationSQL
-     */
-    public function testGeneratesIdentifierNamesInDefaultConstraintDeclarationSQL(
-        string $table,
-        array $column,
-        string $expectedSql
-    ): void {
-        self::assertSame($expectedSql, $this->platform->getDefaultConstraintDeclarationSQL($table, $column));
-    }
-
-    /**
-     * @return mixed[][]
-     */
-    public static function getGeneratesIdentifierNamesInDefaultConstraintDeclarationSQL(): iterable
-    {
-        return [
-            // Unquoted identifiers non-reserved keywords.
-            [
-                'mytable',
-                [
-                    'name' => 'mycolumn',
-                    'default' => 'foo',
-                ],
-                " CONSTRAINT DF_6B2BD609_9BADD926 DEFAULT 'foo' FOR mycolumn",
-            ],
-            // Quoted identifiers non-reserved keywords.
-            [
-                '`mytable`',
-                [
-                    'name' => '`mycolumn`',
-                    'default' => 'foo',
-                ],
-                " CONSTRAINT DF_6B2BD609_9BADD926 DEFAULT 'foo' FOR [mycolumn]",
-            ],
-            // Unquoted identifiers reserved keywords.
-            [
-                'table',
-                [
-                    'name' => 'select',
-                    'default' => 'foo',
-                ],
-                " CONSTRAINT DF_F6298F46_4BF2EAC0 DEFAULT 'foo' FOR [select]",
-            ],
-            // Quoted identifiers reserved keywords.
-            [
-                '`table`',
-                [
-                    'name' => '`select`',
-                    'default' => 'foo',
-                ],
-                " CONSTRAINT DF_F6298F46_4BF2EAC0 DEFAULT 'foo' FOR [select]",
-            ],
-        ];
-    }
-
     /**
      * @param string[] $expectedSql
      *
diff --git a/tests/Platforms/OraclePlatformTest.php b/tests/Platforms/OraclePlatformTest.php
index cc87954460a..28c3b000ad0 100644
--- a/tests/Platforms/OraclePlatformTest.php
+++ b/tests/Platforms/OraclePlatformTest.php
@@ -26,58 +26,6 @@
  */
 class OraclePlatformTest extends AbstractPlatformTestCase
 {
-    /**
-     * @return mixed[][]
-     */
-    public static function dataValidIdentifiers(): iterable
-    {
-        return [
-            ['a'],
-            ['foo'],
-            ['Foo'],
-            ['Foo123'],
-            ['Foo#bar_baz$'],
-            ['"a"'],
-            ['"1"'],
-            ['"foo_bar"'],
-            ['"@$%&!"'],
-        ];
-    }
-
-    /**
-     * @dataProvider dataValidIdentifiers
-     */
-    public function testValidIdentifiers(string $identifier): void
-    {
-        OraclePlatform::assertValidIdentifier($identifier);
-
-        $this->expectNotToPerformAssertions();
-    }
-
-    /**
-     * @return mixed[][]
-     */
-    public static function dataInvalidIdentifiers(): iterable
-    {
-        return [
-            ['1'],
-            ['abc&'],
-            ['abc-def'],
-            ['"'],
-            ['"foo"bar"'],
-        ];
-    }
-
-    /**
-     * @dataProvider dataInvalidIdentifiers
-     */
-    public function testInvalidIdentifiers(string $identifier): void
-    {
-        $this->expectException(Exception::class);
-
-        OraclePlatform::assertValidIdentifier($identifier);
-    }
-
     public function createPlatform(): AbstractPlatform
     {
         return new OraclePlatform();
diff --git a/tests/Schema/SchemaTest.php b/tests/Schema/SchemaTest.php
index 8c9f0be1200..53c0069bd16 100644
--- a/tests/Schema/SchemaTest.php
+++ b/tests/Schema/SchemaTest.php
@@ -27,9 +27,7 @@ public function testAddTable(): void
 
         self::assertTrue($schema->hasTable($tableName));
 
-        $tables = $schema->getTables();
-        self::assertArrayHasKey($tableName, $tables);
-        self::assertSame($table, $tables[$tableName]);
+        self::assertSame([$table], $schema->getTables());
         self::assertSame($table, $schema->getTable($tableName));
         self::assertTrue($schema->hasTable($tableName));
     }
@@ -113,8 +111,7 @@ public function testAddSequences(): void
         self::assertTrue($schema->hasSequence('a_seq'));
         self::assertSame('a_seq', $schema->getSequence('a_seq')->getName());
 
-        $sequences = $schema->getSequences();
-        self::assertArrayHasKey('public.a_seq', $sequences);
+        self::assertEquals([$sequence], $schema->getSequences());
     }
 
     public function testSequenceAccessCaseInsensitive(): void
@@ -151,8 +148,7 @@ public function testCreateSequence(): void
         self::assertTrue($schema->hasSequence('a_seq'));
         self::assertSame('a_seq', $schema->getSequence('a_seq')->getName());
 
-        $sequences = $schema->getSequences();
-        self::assertArrayHasKey('public.a_seq', $sequences);
+        self::assertEquals([$sequence], $schema->getSequences());
     }
 
     public function testDropSequence(): void
@@ -266,7 +262,7 @@ public function testCreatesNamespace(): void
         self::assertTrue($schema->hasNamespace('`bar`'));
         self::assertTrue($schema->hasNamespace('`BAR`'));
 
-        self::assertSame(['foo' => 'foo', 'bar' => '`bar`'], $schema->getNamespaces());
+        self::assertSame(['foo', '`bar`'], $schema->getNamespaces());
     }
 
     public function testThrowsExceptionOnCreatingNamespaceTwice(): void
diff --git a/tests/Schema/TableTest.php b/tests/Schema/TableTest.php
index e39ff9f9c7a..1bc56e423a7 100644
--- a/tests/Schema/TableTest.php
+++ b/tests/Schema/TableTest.php
@@ -594,17 +594,6 @@ public function testQuoteSchemaPrefixed(): void
         self::assertEquals('`test`.`test`', $table->getQuotedName(new MySQLPlatform()));
     }
 
-    public function testFullQualifiedTableName(): void
-    {
-        $table = new Table('`test`.`test`');
-        self::assertEquals('test.test', $table->getFullQualifiedName('test'));
-        self::assertEquals('test.test', $table->getFullQualifiedName('other'));
-
-        $table = new Table('test');
-        self::assertEquals('test.test', $table->getFullQualifiedName('test'));
-        self::assertEquals('other.test', $table->getFullQualifiedName('other'));
-    }
-
     public function testDropIndex(): void
     {
         $table = new Table('test');
diff --git a/tests/Schema/Visitor/RemoveNamespacedAssetsTest.php b/tests/Schema/Visitor/RemoveNamespacedAssetsTest.php
index f01d1c7e606..e4ac1af17c9 100644
--- a/tests/Schema/Visitor/RemoveNamespacedAssetsTest.php
+++ b/tests/Schema/Visitor/RemoveNamespacedAssetsTest.php
@@ -10,8 +10,6 @@
 use Doctrine\DBAL\Schema\Visitor\RemoveNamespacedAssets;
 use PHPUnit\Framework\TestCase;
 
-use function array_keys;
-
 class RemoveNamespacedAssetsTest extends TestCase
 {
     public function testRemoveNamespacedAssets(): void
@@ -26,8 +24,9 @@ public function testRemoveNamespacedAssets(): void
 
         $schema->visit(new RemoveNamespacedAssets());
 
-        $tables = $schema->getTables();
-        self::assertEquals(['test.test', 'test.baz'], array_keys($tables));
+        self::assertTrue($schema->hasTable('test.test'));
+        self::assertTrue($schema->hasTable('test.baz'));
+        self::assertFalse($schema->hasTable('foo.bar'));
     }
 
     public function testCleanupForeignKeys(): void