From 57549fca82a169681ade72240ca349642fd7c918 Mon Sep 17 00:00:00 2001
From: matthewkrausse <106627640+mattkrausse@users.noreply.github.com>
Date: Tue, 20 Feb 2024 15:54:42 -0900
Subject: [PATCH] Add cautionary note about performance in get_row_count method

---
 parsons/google/google_bigquery.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/parsons/google/google_bigquery.py b/parsons/google/google_bigquery.py
index c4002b7997..e08041071d 100644
--- a/parsons/google/google_bigquery.py
+++ b/parsons/google/google_bigquery.py
@@ -1121,6 +1121,10 @@ def get_row_count(self, schema: str, table_name: str) -> int:
         """
         Gets the row count for a BigQuery materialization.
 
+        Caution: This method uses SELECT COUNT(*) which can be expensive for large tables,
+        especially those with many columns. This is because BigQuery scans all table data
+        to perform the count, even though only the row count is returned.
+
         `Args`:
             schema: str
                 The schema name