From 8ffd331c803dbf9de49781efcfbe1f25891be312 Mon Sep 17 00:00:00 2001
From: Alexander Ebert <ebert@woltlab.com>
Date: Fri, 23 Aug 2019 17:49:41 +0200
Subject: [PATCH] Implemented `PreparedStatement::fetchList()`

See #3054
---
 .../statement/PreparedStatement.class.php     | 25 +++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/wcfsetup/install/files/lib/system/database/statement/PreparedStatement.class.php b/wcfsetup/install/files/lib/system/database/statement/PreparedStatement.class.php
index 4abe0333d6..a4b0675b12 100644
--- a/wcfsetup/install/files/lib/system/database/statement/PreparedStatement.class.php
+++ b/wcfsetup/install/files/lib/system/database/statement/PreparedStatement.class.php
@@ -23,7 +23,7 @@ class PreparedStatement {
 	 * database object
 	 * @var	Database
 	 */
-	protected $database = null;
+	protected $database;
 	
 	/**
 	 * SQL query parameters
@@ -35,7 +35,7 @@ class PreparedStatement {
 	 * pdo statement object
 	 * @var	\PDOStatement
 	 */
-	protected $pdoStatement = null;
+	protected $pdoStatement;
 	
 	/**
 	 * SQL query
@@ -221,6 +221,27 @@ class PreparedStatement {
 		return $map;
 	}
 	
+	/**
+	 * Returns a one-dimensional list of all rows holding only the value of the specified column. Please see
+	 * `fetchAll()` if you simply want to read all rows into an array. 
+	 * 
+	 * @param string $column
+	 * @return string[]|int[]|float[]
+	 */
+	public function fetchList($column) {
+		$list = [];
+		
+		while ($row = $this->fetchArray()) {
+			if (!array_key_exists($column, $row)) {
+				throw new \RuntimeException("The requested column '{$column}' is not contained in the result rows.");
+			}
+			
+			$list[] = $row[$column];
+		}
+		
+		return $list;
+	}
+	
 	/**
 	 * Counts number of affected rows by the last sql statement (INSERT, UPDATE or DELETE).
 	 * 
-- 
2.20.1