<?php
declare(strict_types=1);
namespace PhpMyAdmin\Import;
use PhpMyAdmin\Core;
use PhpMyAdmin\DatabaseInterface;
use PhpMyAdmin\Html;
use PhpMyAdmin\SqlParser\Parser;
use PhpMyAdmin\SqlParser\Statement;
use PhpMyAdmin\SqlParser\Statements\DeleteStatement;
use PhpMyAdmin\SqlParser\Statements\UpdateStatement;
use PhpMyAdmin\SqlParser\Utils\Query;
use PhpMyAdmin\Url;
use function implode;
use function strtoupper;
final class SimulateDml
{
/** @var DatabaseInterface */
private $dbi;
public function __construct(DatabaseInterface $dbi)
{
$this->dbi = $dbi;
}
public function getError(): string
{
return $this->dbi->getError();
}
/**
* Find the matching rows for UPDATE/DELETE query.
*
* @param DeleteStatement|UpdateStatement|Statement $statement
*
* @return array<string, int|string>
* @psalm-return array{
* sql_query: string,
* matched_rows: (int|numeric-string),
* matched_rows_url: string
* }
*/
public function getMatchedRows(string $query, Parser $parser, $statement): array
{
$matchedRowQuery = '';
if ($statement instanceof DeleteStatement) {
$matchedRowQuery = $this->getSimulatedDeleteQuery($parser, $statement);
} elseif ($statement instanceof UpdateStatement) {
$matchedRowQuery = $this->getSimulatedUpdateQuery($parser, $statement);
}
// Execute the query and get the number of matched rows.
$matchedRows = $this->executeMatchedRowQuery($matchedRowQuery);
$matchedRowsUrl = Url::getFromRoute('/sql', [
'db' => $GLOBALS['db'],
'sql_query' => $matchedRowQuery,
'sql_signature' => Core::signSqlQuery($matchedRowQuery),
]);
return [
'sql_query' => Html\Generator::formatSql($query),
'matched_rows' => $matchedRows,
'matched_rows_url' => $matchedRowsUrl,
];
}
/**
* Executes the matched_row_query and returns the resultant row count.
*
* @param string $matchedRowQuery SQL query
*
* @return int|string
* @psalm-return int|numeric-string
*/
private function executeMatchedRowQuery(string $matchedRowQuery)
{
$this->dbi->selectDb($GLOBALS['db']);
// Execute the query.
$result = $this->dbi->tryQuery($matchedRowQuery);
if (! $result) {
return 0;
}
// Count the number of rows in the result set.
return $result->numRows();
}
/**
* Transforms a DELETE query into SELECT statement.
*
* @return string SQL query
*/
private function getSimulatedDeleteQuery(Parser $parser, DeleteStatement $statement): string
{
$tableReferences = Query::getTables($statement);
$where = Query::getClause($statement, $parser->list, 'WHERE');
if (empty($where)) {
$where = '1';
}
$orderAndLimit = '';
if (! empty($statement->order)) {
$orderAndLimit .= ' ORDER BY ' . Query::getClause($statement, $parser->list, 'ORDER BY');
}
if (! empty($statement->limit)) {
$orderAndLimit .= ' LIMIT ' . Query::getClause($statement, $parser->list, 'LIMIT');
}
return 'SELECT * FROM ' . implode(', ', $tableReferences) .
' WHERE ' . $where . $orderAndLimit;
}
/**
* Transforms a UPDATE query into SELECT statement.
*
* @return string SQL query
*/
private function getSimulatedUpdateQuery(Parser $parser, UpdateStatement $statement): string
{
$tableReferences = Query::getTables($statement);
$where = Query::getClause($statement, $parser->list, 'WHERE');
if (empty($where)) {
$where = '1';
}
$columns = [];
$diff = [];
foreach ($statement->set as $set) {
$columns[] = $set->column;
$notEqualOperator = ' <> ';
if (strtoupper($set->value) === 'NULL') {
$notEqualOperator = ' IS NOT ';
}
$diff[] = $set->column . $notEqualOperator . $set->value;
}
if (! empty($diff)) {
$where .= ' AND (' . implode(' OR ', $diff) . ')';
}
$orderAndLimit = '';
if (! empty($statement->order)) {
$orderAndLimit .= ' ORDER BY ' . Query::getClause($statement, $parser->list, 'ORDER BY');
}
if (! empty($statement->limit)) {
$orderAndLimit .= ' LIMIT ' . Query::getClause($statement, $parser->list, 'LIMIT');
}
return 'SELECT ' . implode(', ', $columns) .
' FROM ' . implode(', ', $tableReferences) .
' WHERE ' . $where . $orderAndLimit;
}
}