diff --git a/migrations/000.279.sql b/migrations/000.279.sql
new file mode 100644
index 0000000..3583ade
--- /dev/null
+++ b/migrations/000.279.sql
@@ -0,0 +1,27 @@
+-- P5-6109 de_DE fallback locale to de_AT; delete duplicate text tags
+
+-- Make German german the fallback locale of Austrian german
+UPDATE locales
+SET fallback_id = (SELECT id from locales where value = 'de_DE')
+WHERE value = 'de_AT';
+
+
+-- Delete de_AT text tags that are identical to the de_DE version
+-- (except productTitles category which does not support fallback locales yet)
+DELETE FROM "i18n-texts_data"
+WHERE
+	locale_id = (select id from locales where value = 'de_AT')
+	AND textid IN (
+		select
+			at.textid
+		from
+			"i18n-texts_data" at
+			join "i18n-texts_data" de on at.textid = de.textid and de.locale_id = (select id from locales where value = 'de_DE')
+			join "i18n-texts" texts on at.textid = texts.textid
+		where
+			at.locale_id = (select id from locales where value = 'de_AT')
+			and category not in ('productTitles','productDescription')
+			and at.text = de.text
+		order by at.textid
+	)
+;