DataReader::read() - Code Metrics - Inspection of "big refactoring." - yiisoft/db - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Pull Request — master (#266)

by Wilmer

created 2022-02-12 11:52 UTC

DataReader::read() A

↳ Parent: DataReader

Complexity

Conditions	1
Paths	1

Size

Total Lines	3
Code Lines	1

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
cc	1
eloc	1
nc	1
nop	0
dl	0
loc	3
rs	10
c	0
b	0
f	0

<?php

declare(strict_types=1);

namespace Yiisoft\Db\Query\Data;

use Countable;
use Iterator;
use PDO;
use PDOStatement;
use Yiisoft\Db\Command\Command;
use Yiisoft\Db\Exception\InvalidCallException;

use function call_user_func_array;

/**
 * DataReader represents a forward-only stream of rows from a query result set.
 *
 * To read the current row of data, call {@see read()}. The method {@see readAll()} returns all the rows in a single
 * array. Rows of data can also be read by iterating through the reader. For example,
 *
 * ```php
 * $command = $connection->createCommand('SELECT * FROM post');
 * $reader = $command->query();
 *
 * while ($row = $reader->read()) {
 *     $rows[] = $row;
 * }
 *
 * // equivalent to:
 * foreach ($reader as $row) {
 *     $rows[] = $row;
 * }
 *
 * // equivalent to:
 * $rows = $reader->readAll();
 * ```
 *
 * Note that since DataReader is a forward-only stream, you can only traverse it once. Doing it the second time will
 * throw an exception.
 *
 * It is possible to use a specific mode of data fetching by setting {@see fetchMode}. See the
 * [PHP manual](http://www.php.net/manual/en/function.PDOStatement-setFetchMode.php) for more details about possible
 * fetch mode.
 *
 * @property int $columnCount The number of columns in the result set. This property is read-only.
 * @property int $fetchMode Fetch mode. This property is write-only.
 * @property bool $isClosed Whether the reader is closed or not. This property is read-only.
 * @property int $rowCount Number of rows contained in the result. This property is read-only.
 */
final class DataReader implements Iterator, Countable
{
    /** @var mixed @row */
    private $row;
    private PDOStatement $statement;
    private bool $closed = false;
    private int $index = -1;

    public function __construct(Command $command)
    {
        $this->statement = $command->getPDOStatement();
        $this->statement->setFetchMode(PDO::FETCH_ASSOC);
    }

    /**
     * Binds a column to a PHP variable.
     *
     * When rows of data are being fetched, the corresponding column value will be set in the variable. Note, the fetch
     * mode must include {@see PDO::FETCH_BOUND}.
     *
     * @param int|string $column Number of the column (1-indexed) or name of the column in the result set. If using the
     * column name, be aware that the name should match the case of the column, as returned by the driver.
     * @param mixed $value Name of the PHP variable to which the column will be bound.
     * @param int|null $dataType Data type of the parameter.
     *
     * {@see http://www.php.net/manual/en/function.PDOStatement-bindColumn.php}
     */
    public function bindColumn($column, &$value, ?int $dataType = null): void
    {
        if ($dataType === null) {
            $this->statement->bindColumn($column, $value);
        } else {
            $this->statement->bindColumn($column, $value, $dataType);
        }
    }

    /**
     * Set the default fetch mode for this statement.
     *
     * @param int $mode fetch mode.
     *
     * {@see http://www.php.net/manual/en/function.PDOStatement-setFetchMode.php}
     */
    public function setFetchMode(int $mode): void
    {
        $params = func_get_args();
        call_user_func_array([$this->statement, 'setFetchMode'], $params);
    }

    /**
     * Advances the reader to the next row in a result set.
     *
     * @return array|bool the current row, false if no more row available.
     */
    public function read()
    {
        return $this->statement->fetch();
    }

    /**
     * Returns a single column from the next row of a result set.
     *
     * @param int $columnIndex zero-based column index.
     *
     * @return mixed the column of the current row, false if no more rows available.
     */
    public function readColumn(int $columnIndex)
    {
        return $this->statement->fetchColumn($columnIndex);
    }

    /**
     * Returns an object populated with the next row of data.
     *
     * @param string $className class name of the object to be created and populated.
     * @param array $fields Elements of this array are passed to the constructor.
     *
     * @return mixed the populated object, false if no more row of data available.
     */
    public function readObject(string $className, array $fields)
    {
        return $this->statement->fetchObject($className, $fields);
    }

    /**
     * Reads the whole result set into an array.
     *
     * @return array the result set (each array element represents a row of data). An empty array will be returned if
     * the result contains no row.
     */
    public function readAll(): array
    {
        return $this->statement->fetchAll();
    }

    /**
     * Advances the reader to the next result when reading the results of a batch of statements. This method is only
     * useful when there are multiple result sets returned by the query. Not all DBMS support this feature.
     *
     * @return bool Returns true on success or false on failure.
     */
    public function nextResult(): bool
    {
        if (($result = $this->statement->nextRowset()) !== false) {
            $this->index = -1;
        }

        return $result;
    }

    /**
     * Closes the reader.
     *
     * This frees up the resources allocated for executing this SQL statement. Read attempts after this method call are
     * unpredictable.
     */
    public function close(): void
    {
        $this->statement->closeCursor();
        $this->closed = true;
    }

    /**
     * whether the reader is closed or not.
     *
     * @return bool whether the reader is closed or not.
     */
    public function isClosed(): bool
    {
        return $this->closed;
    }

    /**
     * Returns the number of rows in the result set.
     *
     * Note, most DBMS may not give a meaningful count. In this case, use "SELECT COUNT(*) FROM tableName" to obtain the
     * number of rows.
     *
     * @return int number of rows contained in the result.
     */
    public function getRowCount(): int
    {
        return $this->statement->rowCount();
    }

    /**
     * Returns the number of rows in the result set.
     *
     * This method is required by the Countable interface.
     *
     * Note, most DBMS may not give a meaningful count. In this case, use "SELECT COUNT(*) FROM tableName" to obtain the
     * number of rows.
     *
     * @return int number of rows contained in the result.
     */
    public function count(): int
    {
        return $this->getRowCount();
    }

    /**
     * Returns the number of columns in the result set.
     *
     * Note, even there's no row in the reader, this still gives correct column number.
     *
     * @return int the number of columns in the result set.
     */
    public function getColumnCount(): int
    {
        return $this->statement->columnCount();
    }

    /**
     * Resets the iterator to the initial state.
     *
     * This method is required by the interface {@see Iterator}.
     *
     * @throws InvalidCallException
     */
    public function rewind(): void
    {
        if ($this->index < 0) {
            $this->row = $this->statement->fetch();
            $this->index = 0;
        } else {
            throw new InvalidCallException('DataReader cannot rewind. It is a forward-only reader.');
        }
    }

    /**
     * Returns the index of the current row.
     *
     * This method is required by the interface {@see Iterator}.
     *
     * @return int the index of the current row.
     */
    public function key(): int
    {
        return $this->index;
    }

    /**
     * Returns the current row.
     *
     * This method is required by the interface {@see Iterator}.
     *
     * @return mixed the current row.
     */
    #[\ReturnTypeWillChange]
    public function current()
    {
        return $this->row;
    }

    /**
     * Moves the internal pointer to the next row.
     *
     * This method is required by the interface {@see Iterator}.
     */
    public function next(): void
    {
        $this->row = $this->statement->fetch();
        $this->index++;
    }

    /**
     * Returns whether there is a row of data at current position.
     *
     * This method is required by the interface {@see Iterator}.
     *
     * @return bool whether there is a row of data at current position.
     */
    public function valid(): bool
    {
        return $this->row !== false;
    }
}


1			<?php
2
3			declare(strict_types=1);
4
5			namespace Yiisoft\Db\Query\Data;
6
7			use Countable;
8			use Iterator;
9			use PDO;
10			use PDOStatement;
11			use Yiisoft\Db\Command\Command;
12			use Yiisoft\Db\Exception\InvalidCallException;
13
14			use function call_user_func_array;
15
16			/**
17			* DataReader represents a forward-only stream of rows from a query result set.
18			*
19			* To read the current row of data, call {@see read()}. The method {@see readAll()} returns all the rows in a single
20			* array. Rows of data can also be read by iterating through the reader. For example,
21			*
22			* ```php
23			* $command = $connection->createCommand('SELECT * FROM post');
24			* $reader = $command->query();
25			*
26			* while ($row = $reader->read()) {
27			* $rows[] = $row;
28			* }
29			*
30			* // equivalent to:
31			* foreach ($reader as $row) {
32			* $rows[] = $row;
33			* }
34			*
35			* // equivalent to:
36			* $rows = $reader->readAll();
37			* ```
38			*
39			* Note that since DataReader is a forward-only stream, you can only traverse it once. Doing it the second time will
40			* throw an exception.
41			*
42			* It is possible to use a specific mode of data fetching by setting {@see fetchMode}. See the
43			* [PHP manual](http://www.php.net/manual/en/function.PDOStatement-setFetchMode.php) for more details about possible
44			* fetch mode.
45			*
46			* @property int $columnCount The number of columns in the result set. This property is read-only.
47			* @property int $fetchMode Fetch mode. This property is write-only.
48			* @property bool $isClosed Whether the reader is closed or not. This property is read-only.
49			* @property int $rowCount Number of rows contained in the result. This property is read-only.
50			*/
51			final class DataReader implements Iterator, Countable
52			{
53			/** @var mixed @row */
54			private $row;
55			private PDOStatement $statement;
56			private bool $closed = false;
57			private int $index = -1;
58
59			public function __construct(Command $command)
60			{
61			$this->statement = $command->getPDOStatement();
62			$this->statement->setFetchMode(PDO::FETCH_ASSOC);
63			}
64
65			/**
66			* Binds a column to a PHP variable.
67			*
68			* When rows of data are being fetched, the corresponding column value will be set in the variable. Note, the fetch
69			* mode must include {@see PDO::FETCH_BOUND}.
70			*
71			* @param int\|string $column Number of the column (1-indexed) or name of the column in the result set. If using the
72			* column name, be aware that the name should match the case of the column, as returned by the driver.
73			* @param mixed $value Name of the PHP variable to which the column will be bound.
74			* @param int\|null $dataType Data type of the parameter.
75			*
76			* {@see http://www.php.net/manual/en/function.PDOStatement-bindColumn.php}
77			*/
78			public function bindColumn($column, &$value, ?int $dataType = null): void
79			{
80			if ($dataType === null) {
81			$this->statement->bindColumn($column, $value);
82			} else {
83			$this->statement->bindColumn($column, $value, $dataType);
84			}
85			}
86
87			/**
88			* Set the default fetch mode for this statement.
89			*
90			* @param int $mode fetch mode.
91			*
92			* {@see http://www.php.net/manual/en/function.PDOStatement-setFetchMode.php}
93			*/
94			public function setFetchMode(int $mode): void
95			{
96			$params = func_get_args();
97			call_user_func_array([$this->statement, 'setFetchMode'], $params);
98			}
99
100			/**
101			* Advances the reader to the next row in a result set.
102			*
103			* @return array\|bool the current row, false if no more row available.
104			*/
105			public function read()
106			{
107			return $this->statement->fetch();
108			}
109
110			/**
111			* Returns a single column from the next row of a result set.
112			*
113			* @param int $columnIndex zero-based column index.
114			*
115			* @return mixed the column of the current row, false if no more rows available.
116			*/
117			public function readColumn(int $columnIndex)
118			{
119			return $this->statement->fetchColumn($columnIndex);
120			}
121
122			/**
123			* Returns an object populated with the next row of data.
124			*
125			* @param string $className class name of the object to be created and populated.
126			* @param array $fields Elements of this array are passed to the constructor.
127			*
128			* @return mixed the populated object, false if no more row of data available.
129			*/
130			public function readObject(string $className, array $fields)
131			{
132			return $this->statement->fetchObject($className, $fields);
133			}
134
135			/**
136			* Reads the whole result set into an array.
137			*
138			* @return array the result set (each array element represents a row of data). An empty array will be returned if
139			* the result contains no row.
140			*/
141			public function readAll(): array
142			{
143			return $this->statement->fetchAll();
144			}
145
146			/**
147			* Advances the reader to the next result when reading the results of a batch of statements. This method is only
148			* useful when there are multiple result sets returned by the query. Not all DBMS support this feature.
149			*
150			* @return bool Returns true on success or false on failure.
151			*/
152			public function nextResult(): bool
153			{
154			if (($result = $this->statement->nextRowset()) !== false) {
155			$this->index = -1;
156			}
157
158			return $result;
159			}
160
161			/**
162			* Closes the reader.
163			*
164			* This frees up the resources allocated for executing this SQL statement. Read attempts after this method call are
165			* unpredictable.
166			*/
167			public function close(): void
168			{
169			$this->statement->closeCursor();
170			$this->closed = true;
171			}
172
173			/**
174			* whether the reader is closed or not.
175			*
176			* @return bool whether the reader is closed or not.
177			*/
178			public function isClosed(): bool
179			{
180			return $this->closed;
181			}
182
183			/**
184			* Returns the number of rows in the result set.
185			*
186			* Note, most DBMS may not give a meaningful count. In this case, use "SELECT COUNT(*) FROM tableName" to obtain the
187			* number of rows.
188			*
189			* @return int number of rows contained in the result.
190			*/
191			public function getRowCount(): int
192			{
193			return $this->statement->rowCount();
194			}
195
196			/**
197			* Returns the number of rows in the result set.
198			*
199			* This method is required by the Countable interface.
200			*
201			* Note, most DBMS may not give a meaningful count. In this case, use "SELECT COUNT(*) FROM tableName" to obtain the
202			* number of rows.
203			*
204			* @return int number of rows contained in the result.
205			*/
206			public function count(): int
207			{
208			return $this->getRowCount();
209			}
210
211			/**
212			* Returns the number of columns in the result set.
213			*
214			* Note, even there's no row in the reader, this still gives correct column number.
215			*
216			* @return int the number of columns in the result set.
217			*/
218			public function getColumnCount(): int
219			{
220			return $this->statement->columnCount();
221			}
222
223			/**
224			* Resets the iterator to the initial state.
225			*
226			* This method is required by the interface {@see Iterator}.
227			*
228			* @throws InvalidCallException
229			*/
230			public function rewind(): void
231			{
232			if ($this->index < 0) {
233			$this->row = $this->statement->fetch();
234			$this->index = 0;
235			} else {
236			throw new InvalidCallException('DataReader cannot rewind. It is a forward-only reader.');
237			}
238			}
239
240			/**
241			* Returns the index of the current row.
242			*
243			* This method is required by the interface {@see Iterator}.
244			*
245			* @return int the index of the current row.
246			*/
247			public function key(): int
248			{
249			return $this->index;
250			}
251
252			/**
253			* Returns the current row.
254			*
255			* This method is required by the interface {@see Iterator}.
256			*
257			* @return mixed the current row.
258			*/
259			#[\ReturnTypeWillChange]
260			public function current()
261			{
262			return $this->row;
263			}
264
265			/**
266			* Moves the internal pointer to the next row.
267			*
268			* This method is required by the interface {@see Iterator}.
269			*/
270			public function next(): void
271			{
272			$this->row = $this->statement->fetch();
273			$this->index++;
274			}
275
276			/**
277			* Returns whether there is a row of data at current position.
278			*
279			* This method is required by the interface {@see Iterator}.
280			*
281			* @return bool whether there is a row of data at current position.
282			*/
283			public function valid(): bool
284			{
285			return $this->row !== false;
286			}
287			}
288

yiisoft / db

Pull Request — master (#266)

DataReader::read() A

Complexity

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Duplication

Importance

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