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<?php |
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|
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if (!defined('ABSPATH')) { |
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exit; |
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} |
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|
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/** |
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* Plugin-table storage-engine drift correction. |
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* |
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* Walks every plugin table and ALTERs anything that is not InnoDB back to InnoDB. |
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* Plugin tables are uniformly InnoDB by design: crash-safe, no MyISAM "table is full" |
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* (.MYI 4 GiB) failure mode, no table-level locking on high-traffic logsv2 writes. |
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* Hosting migrations and manual SQL restores periodically revert tables to MyISAM; |
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* this component is the centralised place that reverts them back. |
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* |
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* Reachable from {@see ABJ_404_Solution_DatabaseUpgradeSelfHeal::verifyAndRepairCurrentSite()} |
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* and from {@see ABJ_404_Solution_DatabaseUpgradeDailyMaintenance::runDatabaseMaintenanceTasks()} |
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* via the coordinator delegate map. |
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*/ |
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class ABJ_404_Solution_DatabaseUpgradeEngineNormalization extends ABJ_404_Solution_DatabaseUpgradeComponent { |
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|
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/** @return void */ |
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function updateTableEngineToInnoDB() { |
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$result = $this->viewRead->getTableEngines(); |
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$resultRows = isset($result['rows']) && is_array($result['rows']) ? $result['rows'] : []; |
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if (empty($resultRows)) { |
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return; |
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} |
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|
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foreach ($resultRows as $row) { |
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if (!is_array($row)) { |
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continue; |
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} |
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$tableName = array_key_exists('table_name', $row) ? (string)$row['table_name'] : |
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(array_key_exists('TABLE_NAME', $row) ? (string)$row['TABLE_NAME'] : ''); |
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$engine = array_key_exists('engine', $row) ? (string)$row['engine'] : |
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(array_key_exists('ENGINE', $row) ? (string)$row['ENGINE'] : ''); |
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|
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// All plugin tables use InnoDB: crash-safe, no row-count ceiling, no table-level |
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// locking. The former MyISAM special-case for logsv2 ("OPTIMIZE TABLE is slow |
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// otherwise") no longer applies -- OPTIMIZE TABLE on InnoDB has been equivalent to |
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// ALTER TABLE ... ENGINE=InnoDB since MySQL 5.6 (rebuilds tablespace in-place). |
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// InnoDB also eliminates the MyISAM-specific "table is full" failure mode on sites |
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// with disk pressure (MyISAM .MYI files cannot grow past 4 GiB by default). |
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if (strtolower($engine) === 'innodb') { |
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continue; |
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} |
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|
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$this->logger->infoMessage("Updating " . $tableName . " to InnoDB."); |
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$query = 'alter table `' . $tableName . '` engine = InnoDB;'; |
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|
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$result = $this->dbCore->queryAndGetResults($query, array("log_errors" => false)); |
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$this->logger->infoMessage("I changed an engine: " . $query); |
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$lastError = isset($result['last_error']) && is_string($result['last_error']) ? $result['last_error'] : ''; |
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|
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if ($lastError !== '' && |
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strpos($lastError, 'Index column size too large') !== false) { |
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|
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// delete the indexes, try again, and create the indexes later. |
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$this->upgrades()->schemaDiffUpgrade()->deleteIndexes($tableName); |
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|
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$this->dbCore->queryAndGetResults($query, |
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array("ignore_errors" => array("Unknown storage engine"))); |
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$this->logger->infoMessage("I tried to change an engine again: " . $query); |
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} |
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} |
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} |
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} |
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|
