diff --git a/lib/private/DB/QueryBuilder/FunctionBuilder/FunctionBuilder.php b/lib/private/DB/QueryBuilder/FunctionBuilder/FunctionBuilder.php
index f0a809eff35..5c494db7b62 100644
--- a/lib/private/DB/QueryBuilder/FunctionBuilder/FunctionBuilder.php
+++ b/lib/private/DB/QueryBuilder/FunctionBuilder/FunctionBuilder.php
@@ -82,7 +82,7 @@ class FunctionBuilder implements IFunctionBuilder {
 	public function octetLength($field, $alias = ''): IQueryFunction {
 		$alias = $alias ? (' AS ' . $this->helper->quoteColumnName($alias)) : '';
 		$quotedName = $this->helper->quoteColumnName($field);
-		return new QueryFunction('LENGTHB(' . $quotedName . ')' . $alias);
+		return new QueryFunction('OCTET_LENGTH(' . $quotedName . ')' . $alias);
 	}
 
 	public function charLength($field, $alias = ''): IQueryFunction {
diff --git a/lib/private/DB/QueryBuilder/FunctionBuilder/OCIFunctionBuilder.php b/lib/private/DB/QueryBuilder/FunctionBuilder/OCIFunctionBuilder.php
index 5581207a166..5c3c5d327d7 100644
--- a/lib/private/DB/QueryBuilder/FunctionBuilder/OCIFunctionBuilder.php
+++ b/lib/private/DB/QueryBuilder/FunctionBuilder/OCIFunctionBuilder.php
@@ -72,4 +72,10 @@ class OCIFunctionBuilder extends FunctionBuilder {
 
 		return parent::least($x, $y);
 	}
+
+	public function octetLength($field, $alias = ''): IQueryFunction {
+		$alias = $alias ? (' AS ' . $this->helper->quoteColumnName($alias)) : '';
+		$quotedName = $this->helper->quoteColumnName($field);
+		return new QueryFunction('LENGTHB(' . $quotedName . ')' . $alias);
+	}
 }