From 6468c0d7908d30dcf08732903d1773991b54b92d Mon Sep 17 00:00:00 2001
From: dbulahov <bulahovdenis@gmail.com>
Date: Mon, 7 Sep 2026 16:52:58 +0300
Subject: [PATCH] fix DuckDbDialect Signed-off-by: <bulahovdenis@gmail.com>

---
 .../sql/dialect/db/duckdb/DuckDbDialect.java     | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/dialect/db/duckdb/src/main/java/org/eclipse/daanse/sql/dialect/db/duckdb/DuckDbDialect.java b/dialect/db/duckdb/src/main/java/org/eclipse/daanse/sql/dialect/db/duckdb/DuckDbDialect.java
index 6bf591c..9d91c38 100644
--- a/dialect/db/duckdb/src/main/java/org/eclipse/daanse/sql/dialect/db/duckdb/DuckDbDialect.java
+++ b/dialect/db/duckdb/src/main/java/org/eclipse/daanse/sql/dialect/db/duckdb/DuckDbDialect.java
@@ -302,7 +302,7 @@ public java.util.Optional<String> generatePercentileDisc(double percentile, bool
                 .of((buildPercentileFunction("quantile_disc", percentile, desc, tableName, columnName)).toString());
     }
 
-	@Override
+    @Override
     public java.util.Optional<String> generatePercentileCont(double percentile, boolean desc, String tableName,
             String columnName) {
         return java.util.Optional
@@ -331,6 +331,20 @@ public java.util.Optional<String> generateNthValueAgg(CharSequence operand, bool
                 .of((buildNthValueFunction("NTH_VALUE", operand, ignoreNulls, n, columns, false)).toString());
     }
 
+    /**
+     * No.
+     *
+     * <p>
+     * DuckDB, like SQLite, is single-writer: concurrent {@code CREATE TABLE}
+     * transactions from separate connections against the same database
+     * conflict on the shared catalog ("Catalog write-write conflict") instead
+     * of dividing the work.
+     */
+    @Override
+    public boolean supportsParallelLoading() {
+        return false;
+    }
+
     @Override
     public boolean supportsPercentileDisc() {
         return true;