chore: Add TPCDS benchmarks.

Author: comphead

benchmarks/bench.sh

@@ -664,12 +664,22 @@ run_tpcds() {
 
     # Check if TPCDS data directory exists
     if [ ! -d "${TPCDS_DIR}" ]; then
-        echo "Error: TPC-DS data directory does not exist: ${TPCDS_DIR}"
-        echo ""
-        echo "Please prepare TPC-DS data first by running:"
-        echo "  ./bench.sh data tpcds"
-        echo ""
-        return 1
+        echo "Error: TPC-DS data directory does not exist: ${TPCDS_DIR}" >&2
+        echo "" >&2
+        echo "Please prepare TPC-DS data first by following instructions:" >&2
+        echo "  ./bench.sh data tpcds" >&2
+        echo "" >&2
+        exit 1
+    fi
+
+    # Check if directory contains parquet files
+    if ! find "${TPCDS_DIR}" -name "*.parquet" -print -quit | grep -q .; then
+        echo "Error: TPC-DS data directory exists but contains no parquet files: ${TPCDS_DIR}" >&2
+        echo "" >&2
+        echo "Please prepare TPC-DS data first by following instructions:" >&2
+        echo "  ./bench.sh data tpcds" >&2
+        echo "" >&2
+        exit 1
     fi
 
     RESULTS_FILE="${RESULTS_DIR}/tpcds_sf1.json"