diff --git a/doc/topics/strategy-testing.md b/doc/topics/strategy-testing.md
index 05f628c50..7aaaa979c 100644
--- a/doc/topics/strategy-testing.md
+++ b/doc/topics/strategy-testing.md
@@ -1,6 +1,6 @@
 ## Strategy Testing
 
-A pre-built small backtest data db file is located at `data/bbgo_test.sql`.
+A pre-built small backtest data db file is located at `data/bbgo_test.sql`, which contains 30days BTCUSDT kline data from binance.
 
 You can use this file for environments without networking to test your strategy.
 
@@ -11,6 +11,12 @@ A small backtest data set is synchronized in the database:
 - startDate: 2022-06-01
 - endDate: 2022-06-30
 
+The SQL file is added via git-lfs, so you need to install git-lfs first:
+
+```shell
+git lfs install
+```
+
 To import the database, you can do:
 
 ```shell