From 76d746655034d2ab4b2a37ccc4eb3c3a1eef60c9 Mon Sep 17 00:00:00 2001
From: Alexander Ebert <ebert@woltlab.com>
Date: Fri, 27 Jan 2012 18:42:38 +0100
Subject: [PATCH] Implemented support for table conflicts

@Burntime Could you add PostgreSQL support later?

See #178
---
 .../files/lib/system/WCFSetup.class.php       |  4 ++
 .../database/editor/DatabaseEditor.class.php  |  7 +++
 .../editor/MySQLDatabaseEditor.class.php      | 46 +++++++++++++++++++
 .../editor/PostgreSQLDatabaseEditor.class.php |  7 +++
 4 files changed, 64 insertions(+)

diff --git a/wcfsetup/install/files/lib/system/WCFSetup.class.php b/wcfsetup/install/files/lib/system/WCFSetup.class.php
index 579e37fed3..b3716bb7e5 100644
--- a/wcfsetup/install/files/lib/system/WCFSetup.class.php
+++ b/wcfsetup/install/files/lib/system/WCFSetup.class.php
@@ -555,6 +555,10 @@ class WCFSetup extends WCF {
 				
 				// check for table conflicts
 				$conflictedTables = $this->getConflictedTables($db, $dbNumber);
+				if (!empty($conflictedTables) && ($overwriteTables || self::$developerMode)) {
+					// remove tables
+					$db->getEditor()->dropConflictedTables($conflictedTables);
+				}
 				
 				// write config.inc
 				if (empty($conflictedTables) || $overwriteTables || self::$developerMode) {
diff --git a/wcfsetup/install/files/lib/system/database/editor/DatabaseEditor.class.php b/wcfsetup/install/files/lib/system/database/editor/DatabaseEditor.class.php
index 7cd88bc5a0..afdc91ccae 100644
--- a/wcfsetup/install/files/lib/system/database/editor/DatabaseEditor.class.php
+++ b/wcfsetup/install/files/lib/system/database/editor/DatabaseEditor.class.php
@@ -128,4 +128,11 @@ abstract class DatabaseEditor {
 	 * @param	string		$indexName
 	 */
 	public abstract function dropForeignKey($tableName, $indexName);
+	
+	/**
+	 * Drops all given databases.
+	 * 
+	 * @param	array		$conflictedTables
+	 */
+	public abstract function dropConflictedTables(array $conflictedTables);
 }
diff --git a/wcfsetup/install/files/lib/system/database/editor/MySQLDatabaseEditor.class.php b/wcfsetup/install/files/lib/system/database/editor/MySQLDatabaseEditor.class.php
index 53fac0494f..b960268471 100644
--- a/wcfsetup/install/files/lib/system/database/editor/MySQLDatabaseEditor.class.php
+++ b/wcfsetup/install/files/lib/system/database/editor/MySQLDatabaseEditor.class.php
@@ -1,5 +1,6 @@
 <?php
 namespace wcf\system\database\editor;
+use wcf\system\database\util\PreparedStatementConditionBuilder;
 use wcf\system\database\Database;
 
 /**
@@ -228,4 +229,49 @@ class MySQLDatabaseEditor extends DatabaseEditor {
 		
 		return $definition;
 	}
+	
+	/**
+	 * @see	wcf\system\database\editor\DatabaseEditor::dropConflictedTables()
+	 */
+	public function dropConflictedTables(array $conflictedTables) {
+		$tables = array();
+		foreach ($conflictedTables as $tableName) {
+			$tables[$tableName] = array();
+		}
+		
+		// get current database
+		$sql = "SELECT	DATABASE() AS currentDB";
+		$statement = $this->dbObj->prepareStatement($sql);
+		$statement->execute();
+		$row = $statement->fetchArray();
+		$currentDB = $row['currentDB'];
+		
+		// get constraints
+		$conditions = new PreparedStatementConditionBuilder();
+		$conditions->add("TABLE_SCHEMA = ?", array($currentDB));
+		$conditions->add("TABLE_NAME IN (?)", array($conflictedTables));
+		$conditions->add("REFERENCED_TABLE_NAME IS NOT NULL");
+		$conditions->add("CONSTRAINT_NAME LIKE ?", array('%_fk'));
+		
+		$sql = "SELECT	CONSTRAINT_NAME, TABLE_NAME
+			FROM	information_schema.KEY_COLUMN_USAGE
+			".$conditions;
+		$statement = $this->dbObj->prepareStatement($sql);
+		$statement->execute($conditions->getParameters());
+		while ($row = $statement->fetchArray()) {
+			$this->tables[$row['TABLE_NAME']][] = $row['CONSTRAINT_NAME'];
+		}
+		
+		// drop foreign keys
+		foreach ($this->tables as $tableName => $foreignKeys) {
+			foreach ($foreignKeys as $fk) {
+				$this->dropForeignKey($tableName, $fk);
+			}
+		}
+		
+		// drop tables
+		foreach (array_keys($this->tables) as $tableName) {
+			$this->dropTable($tableName);
+		}
+	}
 }
diff --git a/wcfsetup/install/files/lib/system/database/editor/PostgreSQLDatabaseEditor.class.php b/wcfsetup/install/files/lib/system/database/editor/PostgreSQLDatabaseEditor.class.php
index aae7fcb636..3e3b67cc71 100644
--- a/wcfsetup/install/files/lib/system/database/editor/PostgreSQLDatabaseEditor.class.php
+++ b/wcfsetup/install/files/lib/system/database/editor/PostgreSQLDatabaseEditor.class.php
@@ -387,4 +387,11 @@ class PostgreSQLDatabaseEditor extends DatabaseEditor {
 		
 		throw new DatabaseException("Unknown / unsupported data type '".$mySQLType."'", $this->dbObj);
 	}
+	
+	/**
+	 * @see	wcf\system\database\editor\DatabaseEditor::dropConflictedTables()
+	 */
+	public function dropConflictedTables(array $conflictedTables) {
+		die('IMPLEMENT ME: PostgreSQLDatabaseEditor::dropConflictedTables');
+	}
 }
-- 
2.20.1