diff --git a/Postgrest/src/commonMain/kotlin/io/github/jan/supabase/postgrest/query/PostgrestQueryBuilder.kt b/Postgrest/src/commonMain/kotlin/io/github/jan/supabase/postgrest/query/PostgrestQueryBuilder.kt
index 7b06faa3..7b9c832a 100644
--- a/Postgrest/src/commonMain/kotlin/io/github/jan/supabase/postgrest/query/PostgrestQueryBuilder.kt
+++ b/Postgrest/src/commonMain/kotlin/io/github/jan/supabase/postgrest/query/PostgrestQueryBuilder.kt
@@ -78,7 +78,7 @@ class PostgrestQueryBuilder(
         val requestBuilder = UpsertRequestBuilder(postgrest.config.propertyConversionMethod).apply(request)
         val body = postgrest.serializer.encodeToJsonElement(values).jsonArray
         val columns = body.map { it.jsonObject.keys }.flatten().distinct()
-        requestBuilder.params["columns"] = listOf(columns.joinToString(","))
+        if(columns.isNotEmpty()) requestBuilder.params["columns"] = listOf(columns.joinToString(","))
         requestBuilder.onConflict?.let {
             requestBuilder.params["on_conflict"] = listOf(it)
         }
@@ -132,7 +132,7 @@ class PostgrestQueryBuilder(
         val requestBuilder = InsertRequestBuilder(postgrest.config.propertyConversionMethod).apply(request)
         val body = postgrest.serializer.encodeToJsonElement(values).jsonArray
         val columns = body.map { it.jsonObject.keys }.flatten().distinct()
-        requestBuilder.params["columns"] = listOf(columns.joinToString(","))
+        if(columns.isNotEmpty()) requestBuilder.params["columns"] = listOf(columns.joinToString(","))
         val insertRequest = InsertRequest(
             body = body,
             returning = requestBuilder.returning,