Converted Connection and Statement methods which returned false in case of a failure into void

UPGRADE.md

 # Upgrade to 3.0
 
+## BC BREAK `Statement` and `Connection` methods return `void`.
+
+`Connection::connect()`, `Statement::bindParam()`, `::bindValue()`, `::execute()`, `ResultStatement::setFetchMode()` and `::closeCursor()` no longer return a boolean value. They will throw an exception in case of failure.
+
 ## BC BREAK `Statement::rowCount()` is moved.
 
 `Statement::rowCount()` has been moved to the `ResultStatement` interface where it belongs by definition.

lib/Doctrine/DBAL/Cache/ArrayStatement.php

@@ -44,7 +44,7 @@ class ArrayStatement implements IteratorAggregate, ResultStatement
     /**
      * {@inheritdoc}
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
         unset($this->data);
     }
@@ -72,15 +72,13 @@ class ArrayStatement implements IteratorAggregate, ResultStatement
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
         if (count($args) > 0) {
             throw new InvalidArgumentException('Caching layer does not support 2nd/3rd argument to setFetchMode()');
         }
 
         $this->defaultFetchMode = $fetchMode;
-
-        return true;
     }
 
     /**

lib/Doctrine/DBAL/Cache/ResultCacheStatement.php

@@ -75,11 +75,12 @@ class ResultCacheStatement implements IteratorAggregate, ResultStatement
     /**
      * {@inheritdoc}
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
         $this->statement->closeCursor();
+
         if (! $this->emptied || $this->data === null) {
-            return true;
+            return;
         }
 
         $data = $this->resultCache->fetch($this->cacheKey);
@@ -90,8 +91,6 @@ class ResultCacheStatement implements IteratorAggregate, ResultStatement
 
         $this->resultCache->save($this->cacheKey, $data, $this->lifetime);
         unset($this->data);
-
-        return true;
     }
 
     /**
@@ -105,11 +104,9 @@ class ResultCacheStatement implements IteratorAggregate, ResultStatement
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
         $this->defaultFetchMode = $fetchMode;
-
-        return true;
     }
 
     /**

lib/Doctrine/DBAL/Connection.php

@@ -346,13 +346,12 @@ class Connection implements DriverConnection
     /**
      * Establishes the connection with the database.
      *
-     * @return bool TRUE if the connection was successfully established, FALSE if
-     *              the connection is already open.
+     * @throws DriverException
      */
-    public function connect()
+    public function connect() : void
     {
         if ($this->isConnected) {
-            return false;
+            return;
         }
 
         $driverOptions = $this->params['driverOptions'] ?? [];
@@ -368,12 +367,12 @@ class Connection implements DriverConnection
             $this->beginTransaction();
         }
 
-        if ($this->_eventManager->hasListeners(Events::postConnect)) {
-            $eventArgs = new Event\ConnectionEventArgs($this);
-            $this->_eventManager->dispatchEvent(Events::postConnect, $eventArgs);
+        if (! $this->_eventManager->hasListeners(Events::postConnect)) {
+            return;
         }
 
-        return true;
+        $eventArgs = new Event\ConnectionEventArgs($this);
+        $this->_eventManager->dispatchEvent(Events::postConnect, $eventArgs);
     }
 
     /**
@@ -527,10 +526,8 @@ class Connection implements DriverConnection
      * Sets the fetch mode.
      *
      * @param int $fetchMode
-     *
-     * @return void
      */
-    public function setFetchMode($fetchMode)
+    public function setFetchMode($fetchMode) : void
     {
         $this->defaultFetchMode = $fetchMode;
     }

lib/Doctrine/DBAL/Connections/MasterSlaveConnection.php

@@ -123,7 +123,7 @@ class MasterSlaveConnection extends Connection
     /**
      * {@inheritDoc}
      */
-    public function connect($connectionName = null)
+    public function connect($connectionName = null) : void
     {
         $requestedConnectionChange = ($connectionName !== null);
         $connectionName            = $connectionName ?: 'slave';
@@ -136,7 +136,7 @@ class MasterSlaveConnection extends Connection
         // change request, then abort right here, because we are already done.
         // This prevents writes to the slave in case of "keepSlave" option enabled.
         if ($this->_conn !== null && ! $requestedConnectionChange) {
-            return false;
+            return;
         }
 
         $forceMasterAsSlave = false;
@@ -153,7 +153,7 @@ class MasterSlaveConnection extends Connection
                 $this->connections['slave'] = $this->_conn;
             }
 
-            return false;
+            return;
         }
 
         if ($connectionName === 'master') {
@@ -167,12 +167,12 @@ class MasterSlaveConnection extends Connection
             $this->connections['slave'] = $this->_conn = $this->connectTo($connectionName);
         }
 
-        if ($this->_eventManager->hasListeners(Events::postConnect)) {
-            $eventArgs = new ConnectionEventArgs($this);
-            $this->_eventManager->dispatchEvent(Events::postConnect, $eventArgs);
+        if (! $this->_eventManager->hasListeners(Events::postConnect)) {
+            return;
         }
 
-        return true;
+        $eventArgs = new ConnectionEventArgs($this);
+        $this->_eventManager->dispatchEvent(Events::postConnect, $eventArgs);
     }
 
     /**

lib/Doctrine/DBAL/Driver/IBMDB2/DB2Statement.php

@@ -89,15 +89,15 @@ class DB2Statement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function bindValue($param, $value, $type = ParameterType::STRING)
+    public function bindValue($param, $value, $type = ParameterType::STRING) : void
     {
-        return $this->bindParam($param, $value, $type);
+        $this->bindParam($param, $value, $type);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null)
+    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null) : void
     {
         switch ($type) {
             case ParameterType::INTEGER:
@@ -122,8 +122,6 @@ class DB2Statement implements IteratorAggregate, Statement
                 $this->bind($column, $variable, DB2_PARAM_IN, DB2_CHAR);
                 break;
         }
-
-        return true;
     }
 
     /**
@@ -144,17 +142,17 @@ class DB2Statement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
         $this->bindParam = [];
 
-        if (! db2_free_result($this->stmt)) {
-            return false;
+        if (! $this->result) {
+            return;
         }
 
-        $this->result = false;
+        db2_free_result($this->stmt);
 
-        return true;
+        $this->result = false;
     }
 
     /**
@@ -187,7 +185,7 @@ class DB2Statement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function execute($params = null)
+    public function execute($params = null) : void
     {
         if ($params === null) {
             ksort($this->bindParam);
@@ -222,14 +220,12 @@ class DB2Statement implements IteratorAggregate, Statement
         }
 
         $this->result = true;
-
-        return $retval;
     }
 
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
         $this->defaultFetchMode = $fetchMode;
 
@@ -237,11 +233,11 @@ class DB2Statement implements IteratorAggregate, Statement
             $this->defaultFetchClass = $args[0];
         }
 
-        if (isset($args[1])) {
-            $this->defaultFetchClassCtorArgs = (array) $args[2];
+        if (! isset($args[1])) {
+            return;
         }
 
-        return true;
+        $this->defaultFetchClassCtorArgs = (array) $args[2];
     }
 
     /**

lib/Doctrine/DBAL/Driver/Mysqli/MysqliStatement.php

@@ -3,6 +3,7 @@
 namespace Doctrine\DBAL\Driver\Mysqli;
 
 use Doctrine\DBAL\DBALException;
+use Doctrine\DBAL\Driver\DriverException;
 use Doctrine\DBAL\Driver\Statement;
 use Doctrine\DBAL\Driver\StatementIterator;
 use Doctrine\DBAL\Exception\InvalidArgumentException;
@@ -101,7 +102,7 @@ class MysqliStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null)
+    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null) : void
     {
         assert(is_int($column));
 
@@ -111,14 +112,12 @@ class MysqliStatement implements IteratorAggregate, Statement
 
         $this->_bindedValues[$column] =& $variable;
         $this->types[$column - 1]     = self::$_paramTypeMap[$type];
-
-        return true;
     }
 
     /**
      * {@inheritdoc}
      */
-    public function bindValue($param, $value, $type = ParameterType::STRING)
+    public function bindValue($param, $value, $type = ParameterType::STRING) : void
     {
         assert(is_int($param));
 
@@ -129,14 +128,12 @@ class MysqliStatement implements IteratorAggregate, Statement
         $this->_values[$param]       = $value;
         $this->_bindedValues[$param] =& $this->_values[$param];
         $this->types[$param - 1]     = self::$_paramTypeMap[$type];
-
-        return true;
     }
 
     /**
      * {@inheritdoc}
      */
-    public function execute($params = null)
+    public function execute($params = null) : void
     {
         if ($params !== null && count($params) > 0) {
             if (! $this->bindUntypedValues($params)) {
@@ -199,12 +196,12 @@ class MysqliStatement implements IteratorAggregate, Statement
         }
 
         $this->result = true;
-
-        return true;
     }
 
     /**
      * Binds parameters with known types previously bound to the statement
+     *
+     * @throws DriverException
      */
     private function bindTypedParameters()
     {
@@ -408,12 +405,10 @@ class MysqliStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
         $this->_stmt->free_result();
         $this->result = false;
-
-        return true;
     }
 
     /**
@@ -439,11 +434,9 @@ class MysqliStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
         $this->_defaultFetchMode = $fetchMode;
-
-        return true;
     }
 
     /**

lib/Doctrine/DBAL/Driver/OCI8/OCI8Statement.php

@@ -268,15 +268,15 @@ class OCI8Statement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function bindValue($param, $value, $type = ParameterType::STRING)
+    public function bindValue($param, $value, $type = ParameterType::STRING) : void
     {
-        return $this->bindParam($param, $value, $type, null);
+        $this->bindParam($param, $value, $type, null);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null)
+    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null) : void
     {
         $column = $this->_paramMap[$column];
 
@@ -293,13 +293,15 @@ class OCI8Statement implements IteratorAggregate, Statement
 
         $this->boundValues[$column] =& $variable;
 
-        return oci_bind_by_name(
+        if (! oci_bind_by_name(
             $this->_sth,
             $column,
             $variable,
             $length ?? -1,
             $this->convertParameterType($type)
-        );
+        )) {
+            throw OCI8Exception::fromErrorInfo($this->errorInfo());
+        }
     }
 
     /**
@@ -322,18 +324,16 @@ class OCI8Statement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
         // not having the result means there's nothing to close
         if (! $this->result) {
-            return true;
+            return;
         }
 
         oci_cancel($this->_sth);
 
         $this->result = false;
-
-        return true;
     }
 
     /**
@@ -374,7 +374,7 @@ class OCI8Statement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function execute($params = null)
+    public function execute($params = null) : void
     {
         if ($params) {
             $hasZeroIndex = array_key_exists(0, $params);
@@ -386,9 +386,7 @@ class OCI8Statement implements IteratorAggregate, Statement
                     $param = $key;
                 }
 
-                if (! $this->bindValue($param, $val)) {
-                    throw OCI8Exception::fromErrorInfo($this->errorInfo());
-                }
+                $this->bindValue($param, $val);
             }
         }
 
@@ -398,18 +396,14 @@ class OCI8Statement implements IteratorAggregate, Statement
         }
 
         $this->result = true;
-
-        return $ret;
     }
 
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
         $this->_defaultFetchMode = $fetchMode;
-
-        return true;
     }
 
     /**

lib/Doctrine/DBAL/Driver/PDOSqlsrv/Statement.php

@@ -14,7 +14,7 @@ class Statement extends PDOStatement
     /**
      * {@inheritdoc}
      */
-    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null, $driverOptions = null)
+    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null, $driverOptions = null) : void
     {
         if (($type === ParameterType::LARGE_OBJECT || $type === ParameterType::BINARY)
             && $driverOptions === null
@@ -22,14 +22,14 @@ class Statement extends PDOStatement
             $driverOptions = PDO::SQLSRV_ENCODING_BINARY;
         }
 
-        return parent::bindParam($column, $variable, $type, $length, $driverOptions);
+        parent::bindParam($column, $variable, $type, $length, $driverOptions);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function bindValue($param, $value, $type = ParameterType::STRING)
+    public function bindValue($param, $value, $type = ParameterType::STRING) : void
     {
-        return $this->bindParam($param, $value, $type);
+        $this->bindParam($param, $value, $type);
     }
 }

lib/Doctrine/DBAL/Driver/PDOStatement.php

@@ -50,12 +50,12 @@ class PDOStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
         $fetchMode = $this->convertFetchMode($fetchMode);
 
         try {
-            return $this->stmt->setFetchMode($fetchMode, ...$args);
+            $this->stmt->setFetchMode($fetchMode, ...$args);
         } catch (\PDOException $exception) {
             throw new PDOException($exception);
         }
@@ -64,12 +64,12 @@ class PDOStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function bindValue($param, $value, $type = ParameterType::STRING)
+    public function bindValue($param, $value, $type = ParameterType::STRING) : void
     {
         $type = $this->convertParamType($type);
 
         try {
-            return $this->stmt->bindValue($param, $value, $type);
+            $this->stmt->bindValue($param, $value, $type);
         } catch (\PDOException $exception) {
             throw new PDOException($exception);
         }
@@ -78,12 +78,12 @@ class PDOStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null, $driverOptions = null)
+    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null, $driverOptions = null) : void
     {
         $type = $this->convertParamType($type);
 
         try {
-            return $this->stmt->bindParam($column, $variable, $type, ...array_slice(func_get_args(), 3));
+            $this->stmt->bindParam($column, $variable, $type, ...array_slice(func_get_args(), 3));
         } catch (\PDOException $exception) {
             throw new PDOException($exception);
         }
@@ -92,15 +92,9 @@ class PDOStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
-        try {
-            return $this->stmt->closeCursor();
-        } catch (\PDOException $exception) {
-            // Exceptions not allowed by the interface.
-            // In case driver implementations do not adhere to the interface, silence exceptions here.
-            return true;
-        }
+        $this->stmt->closeCursor();
     }
 
     /**
@@ -130,10 +124,10 @@ class PDOStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function execute($params = null)
+    public function execute($params = null) : void
     {
         try {
-            return $this->stmt->execute($params);
+            $this->stmt->execute($params);
         } catch (\PDOException $exception) {
             throw new PDOException($exception);
         }

lib/Doctrine/DBAL/Driver/ResultStatement.php

@@ -11,10 +11,8 @@ interface ResultStatement extends Traversable
 {
     /**
      * Closes the cursor, enabling the statement to be executed again.
-     *
-     * @return bool TRUE on success or FALSE on failure.
      */
-    public function closeCursor();
+    public function closeCursor() : void;
 
     /**
      * Returns the number of columns in the result set
@@ -42,10 +40,8 @@ interface ResultStatement extends Traversable
      * @param int   $fetchMode Controls how the next row will be returned to the caller.
      *                         The value must be one of the {@link \Doctrine\DBAL\FetchMode} constants.
      * @param mixed ...$args   Optional mode-specific arguments (see {@link self::fetchAll()}).
-     *
-     * @return bool
      */
-    public function setFetchMode($fetchMode, ...$args);
+    public function setFetchMode($fetchMode, ...$args) : void;
 
     /**
      * Returns the next row of a result set.

lib/Doctrine/DBAL/Driver/SQLAnywhere/SQLAnywhereStatement.php

@@ -89,7 +89,7 @@ class SQLAnywhereStatement implements IteratorAggregate, Statement
      *
      * @throws SQLAnywhereException
      */
-    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null)
+    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null) : void
     {
         switch ($type) {
             case ParameterType::INTEGER:
@@ -116,30 +116,22 @@ class SQLAnywhereStatement implements IteratorAggregate, Statement
         if (! sasql_stmt_bind_param_ex($this->stmt, $column - 1, $variable, $type, $variable === null)) {
             throw SQLAnywhereException::fromSQLAnywhereError($this->conn, $this->stmt);
         }
-
-        return true;
     }
 
     /**
      * {@inheritdoc}
      */
-    public function bindValue($param, $value, $type = ParameterType::STRING)
+    public function bindValue($param, $value, $type = ParameterType::STRING) : void
     {
-        return $this->bindParam($param, $value, $type);
+        $this->bindParam($param, $value, $type);
     }
 
     /**
      * {@inheritdoc}
-     *
-     * @throws SQLAnywhereException
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
-        if (! sasql_stmt_reset($this->stmt)) {
-            throw SQLAnywhereException::fromSQLAnywhereError($this->conn, $this->stmt);
-        }
-
-        return true;
+        sasql_stmt_reset($this->stmt);
     }
 
     /**
@@ -171,7 +163,7 @@ class SQLAnywhereStatement implements IteratorAggregate, Statement
      *
      * @throws SQLAnywhereException
      */
-    public function execute($params = null)
+    public function execute($params = null) : void
     {
         if (is_array($params)) {
             $hasZeroIndex = array_key_exists(0, $params);
@@ -190,8 +182,6 @@ class SQLAnywhereStatement implements IteratorAggregate, Statement
         }
 
         $this->result = sasql_stmt_result_metadata($this->stmt);
-
-        return true;
     }
 
     /**
@@ -309,7 +299,7 @@ class SQLAnywhereStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
         $this->defaultFetchMode = $fetchMode;
 
@@ -317,11 +307,11 @@ class SQLAnywhereStatement implements IteratorAggregate, Statement
             $this->defaultFetchClass = $args[0];
         }
 
-        if (isset($args[1])) {
-            $this->defaultFetchClassCtorArgs = (array) $args[1];
+        if (! isset($args[1])) {
+            return;
         }
 
-        return true;
+        $this->defaultFetchClassCtorArgs = (array) $args[1];
     }
 
     /**

lib/Doctrine/DBAL/Driver/SQLSrv/SQLSrvStatement.php

@@ -147,7 +147,7 @@ class SQLSrvStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function bindValue($param, $value, $type = ParameterType::STRING)
+    public function bindValue($param, $value, $type = ParameterType::STRING) : void
     {
         if (! is_numeric($param)) {
             throw new SQLSrvException(
@@ -162,7 +162,7 @@ class SQLSrvStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null)
+    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null) : void
     {
         if (! is_numeric($column)) {
             throw new SQLSrvException('sqlsrv does not support named parameters to queries, use question mark (?) placeholders instead.');
@@ -178,11 +178,11 @@ class SQLSrvStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
         // not having the result means there's nothing to close
         if ($this->stmt === null || ! $this->result) {
-            return true;
+            return;
         }
 
         // emulate it by fetching and discarding rows, similarly to what PDO does in this case
@@ -193,8 +193,6 @@ class SQLSrvStatement implements IteratorAggregate, Statement
         }
 
         $this->result = false;
-
-        return true;
     }
 
     /**
@@ -233,7 +231,7 @@ class SQLSrvStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function execute($params = null)
+    public function execute($params = null) : void
     {
         if ($params) {
             $hasZeroIndex = array_key_exists(0, $params);
@@ -312,7 +310,7 @@ class SQLSrvStatement implements IteratorAggregate, Statement
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
         $this->defaultFetchMode = $fetchMode;
 
@@ -320,11 +318,11 @@ class SQLSrvStatement implements IteratorAggregate, Statement
             $this->defaultFetchClass = $args[0];
         }
 
-        if (isset($args[1])) {
-            $this->defaultFetchClassCtorArgs = (array) $args[1];
+        if (! isset($args[1])) {
+            return;
         }
 
-        return true;
+        $this->defaultFetchClassCtorArgs = (array) $args[1];
     }
 
     /**

lib/Doctrine/DBAL/Driver/Statement.php

@@ -26,9 +26,9 @@ interface Statement extends ResultStatement
      * @param int   $type  Explicit data type for the parameter using the {@link \Doctrine\DBAL\ParameterType}
      *                     constants.
      *
-     * @return bool TRUE on success or FALSE on failure.
+     * @throws DriverException
      */
-    public function bindValue($param, $value, $type = ParameterType::STRING);
+    public function bindValue($param, $value, $type = ParameterType::STRING) : void;
 
     /**
      * Binds a PHP variable to a corresponding named (not supported by mysqli driver, see comment below) or question
@@ -53,9 +53,9 @@ interface Statement extends ResultStatement
      * @param int|null $length   You must specify maxlength when using an OUT bind
      *                           so that PHP allocates enough memory to hold the returned value.
      *
-     * @return bool TRUE on success or FALSE on failure.
+     * @throws DriverException
      */
-    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null);
+    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null) : void;
 
     /**
      * Fetches the SQLSTATE associated with the last operation on the statement handle.
@@ -85,7 +85,7 @@ interface Statement extends ResultStatement
      * @param mixed[]|null $params An array of values with as many elements as there are
      *                             bound parameters in the SQL statement being executed.
      *
-     * @return bool TRUE on success or FALSE on failure.
+     * @throws DriverException
      */
-    public function execute($params = null);
+    public function execute($params = null) : void;
 }

lib/Doctrine/DBAL/Portability/Connection.php

@@ -39,11 +39,16 @@ class Connection extends \Doctrine\DBAL\Connection
     /**
      * {@inheritdoc}
      */
-    public function connect()
+    public function connect() : void
     {
-        $ret = parent::connect();
-        if ($ret) {
+        if ($this->isConnected()) {
+            return;
+        }
+
+        parent::connect();
+
         $params = $this->getParams();
+
         if (isset($params['portability'])) {
             if ($this->getDatabasePlatform()->getName() === 'oracle') {
                 $params['portability'] &= self::PORTABILITY_ORACLE;
@@ -63,7 +68,10 @@ class Connection extends \Doctrine\DBAL\Connection
             $this->portability = $params['portability'];
         }
 
-            if (isset($params['fetch_case']) && $this->portability & self::PORTABILITY_FIX_CASE) {
+        if (! isset($params['fetch_case']) || ! ($this->portability & self::PORTABILITY_FIX_CASE)) {
+            return;
+        }
+
         if ($this->_conn instanceof PDOConnection) {
             // make use of c-level support for case handling
             $this->_conn->getWrappedConnection()->setAttribute(PDO::ATTR_CASE, $params['fetch_case']);
@@ -71,10 +79,6 @@ class Connection extends \Doctrine\DBAL\Connection
             $this->case = $params['fetch_case'] === ColumnCase::LOWER ? CASE_LOWER : CASE_UPPER;
         }
     }
-        }
-
-        return $ret;
-    }
 
     /**
      * @return int

lib/Doctrine/DBAL/Portability/Statement.php

@@ -45,29 +45,29 @@ class Statement implements IteratorAggregate, DriverStatement
     /**
      * {@inheritdoc}
      */
-    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null)
+    public function bindParam($column, &$variable, $type = ParameterType::STRING, $length = null) : void
     {
         assert($this->stmt instanceof DriverStatement);
 
-        return $this->stmt->bindParam($column, $variable, $type, $length);
+        $this->stmt->bindParam($column, $variable, $type, $length);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function bindValue($param, $value, $type = ParameterType::STRING)
+    public function bindValue($param, $value, $type = ParameterType::STRING) : void
     {
         assert($this->stmt instanceof DriverStatement);
 
-        return $this->stmt->bindValue($param, $value, $type);
+        $this->stmt->bindValue($param, $value, $type);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
-        return $this->stmt->closeCursor();
+        $this->stmt->closeCursor();
     }
 
     /**
@@ -101,21 +101,21 @@ class Statement implements IteratorAggregate, DriverStatement
     /**
      * {@inheritdoc}
      */
-    public function execute($params = null)
+    public function execute($params = null) : void
     {
         assert($this->stmt instanceof DriverStatement);
 
-        return $this->stmt->execute($params);
+        $this->stmt->execute($params);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
         $this->defaultFetchMode = $fetchMode;
 
-        return $this->stmt->setFetchMode($fetchMode, ...$args);
+        $this->stmt->setFetchMode($fetchMode, ...$args);
     }
 
     /**

lib/Doctrine/DBAL/Sharding/PoolingShardConnection.php

@@ -166,18 +166,16 @@ class PoolingShardConnection extends Connection
      *
      * @param string|int|null $shardId
      *
-     * @return bool
-     *
      * @throws ShardingException
      */
-    public function connect($shardId = null)
+    public function connect($shardId = null) : void
     {
         if ($shardId === null && $this->_conn) {
-            return false;
+            return;
         }
 
         if ($shardId !== null && $shardId === $this->activeShardId) {
-            return false;
+            return;
         }
 
         if ($this->getTransactionNestingLevel() > 0) {
@@ -189,17 +187,17 @@ class PoolingShardConnection extends Connection
         if (isset($this->activeConnections[$activeShardId])) {
             $this->_conn = $this->activeConnections[$activeShardId];
 
-            return false;
+            return;
         }
 
         $this->_conn = $this->activeConnections[$activeShardId] = $this->connectTo($activeShardId);
 
-        if ($this->_eventManager->hasListeners(Events::postConnect)) {
-            $eventArgs = new ConnectionEventArgs($this);
-            $this->_eventManager->dispatchEvent(Events::postConnect, $eventArgs);
+        if (! $this->_eventManager->hasListeners(Events::postConnect)) {
+            return;
         }
 
-        return true;
+        $eventArgs = new ConnectionEventArgs($this);
+        $this->_eventManager->dispatchEvent(Events::postConnect, $eventArgs);
     }
 
     /**

lib/Doctrine/DBAL/Statement.php

@@ -2,6 +2,7 @@
 
 namespace Doctrine\DBAL;
 
+use Doctrine\DBAL\Driver\DriverException;
 use Doctrine\DBAL\Driver\Statement as DriverStatement;
 use Doctrine\DBAL\Platforms\AbstractPlatform;
 use Doctrine\DBAL\Types\Type;
@@ -84,16 +85,18 @@ class Statement implements IteratorAggregate, DriverStatement
      * @param mixed      $value The value of the parameter.
      * @param mixed      $type  Either a PDO binding type or a DBAL mapping type name or instance.
      *
-     * @return bool TRUE on success, FALSE on failure.
+     * @throws DBALException
+     * @throws DriverException
      */
-    public function bindValue($name, $value, $type = ParameterType::STRING)
+    public function bindValue($name, $value, $type = ParameterType::STRING) : void
     {
         $this->params[$name] = $value;
         $this->types[$name]  = $type;
-        if ($type !== null) {
+
         if (is_string($type)) {
             $type = Type::getType($type);
         }
+
         if ($type instanceof Type) {
             $value       = $type->convertToDatabaseValue($value, $this->platform);
             $bindingType = $type->getBindingType();
@@ -101,10 +104,7 @@ class Statement implements IteratorAggregate, DriverStatement
             $bindingType = $type;
         }
 
-            return $this->stmt->bindValue($name, $value, $bindingType);
-        }
-
-        return $this->stmt->bindValue($name, $value);
+        $this->stmt->bindValue($name, $value, $bindingType);
     }
 
     /**
@@ -118,26 +118,22 @@ class Statement implements IteratorAggregate, DriverStatement
      * @param int|null   $length Must be specified when using an OUT bind
      *                           so that PHP allocates enough memory to hold the returned value.
      *
-     * @return bool TRUE on success, FALSE on failure.
+     * @throws DriverException
      */
-    public function bindParam($name, &$var, $type = ParameterType::STRING, $length = null)
+    public function bindParam($name, &$var, $type = ParameterType::STRING, $length = null) : void
     {
         $this->params[$name] = $var;
         $this->types[$name]  = $type;
 
-        return $this->stmt->bindParam($name, $var, $type, $length);
+        $this->stmt->bindParam($name, $var, $type, $length);
     }
 
     /**
-     * Executes the statement with the currently bound parameters.
-     *
-     * @param mixed[]|null $params
-     *
-     * @return bool TRUE on success, FALSE on failure.
+     * {@inheritDoc}
      *
      * @throws DBALException
      */
-    public function execute($params = null)
+    public function execute($params = null) : void
     {
         if (is_array($params)) {
             $this->params = $params;
@@ -147,32 +143,28 @@ class Statement implements IteratorAggregate, DriverStatement
         $logger->startQuery($this->sql, $this->params, $this->types);
 
         try {
-            $stmt = $this->stmt->execute($params);
+            $this->stmt->execute($params);
         } catch (Throwable $ex) {
-            $logger->stopQuery();
             throw DBALException::driverExceptionDuringQuery(
                 $this->conn->getDriver(),
                 $ex,
                 $this->sql,
                 $this->conn->resolveParams($this->params, $this->types)
             );
+        } finally {
+            $logger->stopQuery();
         }
 
-        $logger->stopQuery();
         $this->params = [];
         $this->types  = [];
-
-        return $stmt;
     }
 
     /**
-     * Closes the cursor, freeing the database resources used by this statement.
-     *
-     * @return bool TRUE on success, FALSE on failure.
+     * {@inheritDoc}
      */
-    public function closeCursor()
+    public function closeCursor() : void
     {
-        return $this->stmt->closeCursor();
+        $this->stmt->closeCursor();
     }
 
     /**
@@ -206,9 +198,9 @@ class Statement implements IteratorAggregate, DriverStatement
     /**
      * {@inheritdoc}
      */
-    public function setFetchMode($fetchMode, ...$args)
+    public function setFetchMode($fetchMode, ...$args) : void
     {
-        return $this->stmt->setFetchMode($fetchMode, ...$args);
+        $this->stmt->setFetchMode($fetchMode, ...$args);
     }
 
     /**

tests/Doctrine/Tests/DBAL/Functional/ConnectionTest.php

@@ -316,7 +316,9 @@ class ConnectionTest extends DbalFunctionalTestCase
             $this->connection->getEventManager()
         );
 
-        self::assertTrue($connection->connect());
+        $connection->connect();
+
+        self::assertTrue($connection->isConnected());
 
         $connection->close();
     }

tests/Doctrine/Tests/DBAL/Functional/StatementTest.php

@@ -241,8 +241,11 @@ EOF
 
     public function testCloseCursorOnNonExecutedStatement() : void
     {
+        $this->expectNotToPerformAssertions();
+
         $stmt = $this->connection->prepare('SELECT id FROM stmt_test');
-        self::assertTrue($stmt->closeCursor());
+
+        $stmt->closeCursor();
     }
 
     /**
@@ -250,12 +253,23 @@ EOF
      */
     public function testCloseCursorAfterCursorEnd() : void
     {
+        $this->expectNotToPerformAssertions();
+
         $stmt = $this->connection->prepare('SELECT name FROM stmt_test');
 
         $stmt->execute();
         $stmt->fetch();
 
-        self::assertTrue($stmt->closeCursor());
+        $stmt->closeCursor();
+    }
+
+    public function testCloseCursorAfterClosingCursor() : void
+    {
+        $this->expectNotToPerformAssertions();
+
+        $stmt = $this->connection->executeQuery('SELECT name FROM stmt_test');
+        $stmt->closeCursor();
+        $stmt->closeCursor();
     }
 
     /**

tests/Doctrine/Tests/DBAL/Portability/StatementTest.php

@@ -45,10 +45,9 @@ class StatementTest extends DbalTestCase
 
         $this->wrappedStmt->expects($this->once())
             ->method('bindParam')
-            ->with($column, $variable, $type, $length)
-            ->will($this->returnValue(true));
+            ->with($column, $variable, $type, $length);
 
-        self::assertTrue($this->stmt->bindParam($column, $variable, $type, $length));
+        $this->stmt->bindParam($column, $variable, $type, $length);
     }
 
     public function testBindValue() : void
@@ -59,19 +58,17 @@ class StatementTest extends DbalTestCase
 
         $this->wrappedStmt->expects($this->once())
             ->method('bindValue')
-            ->with($param, $value, $type)
-            ->will($this->returnValue(true));
+            ->with($param, $value, $type);
 
-        self::assertTrue($this->stmt->bindValue($param, $value, $type));
+        $this->stmt->bindValue($param, $value, $type);
     }
 
     public function testCloseCursor() : void
     {
         $this->wrappedStmt->expects($this->once())
-            ->method('closeCursor')
-            ->will($this->returnValue(true));
+            ->method('closeCursor');
 
-        self::assertTrue($this->stmt->closeCursor());
+        $this->stmt->closeCursor();
     }
 
     public function testColumnCount() : void
@@ -116,10 +113,9 @@ class StatementTest extends DbalTestCase
 
         $this->wrappedStmt->expects($this->once())
             ->method('execute')
-            ->with($params)
-            ->will($this->returnValue(true));
+            ->with($params);
 
-        self::assertTrue($this->stmt->execute($params));
+        $this->stmt->execute($params);
     }
 
     public function testSetFetchMode() : void
@@ -137,7 +133,7 @@ class StatementTest extends DbalTestCase
         $re->setAccessible(true);
 
         self::assertSame(FetchMode::MIXED, $re->getValue($this->stmt));
-        self::assertTrue($this->stmt->setFetchMode($fetchMode, $arg1, $arg2));
+        $this->stmt->setFetchMode($fetchMode, $arg1, $arg2);
         self::assertSame($fetchMode, $re->getValue($this->stmt));
     }