diff --git a/数据库/头歌/带限制条件的查询和表达式查询/带限制条件的查询和表达式查询.sh b/数据库/头歌/带限制条件的查询和表达式查询/带限制条件的查询和表达式查询.sh
new file mode 100644
index 0000000..38b928a
--- /dev/null
+++ b/数据库/头歌/带限制条件的查询和表达式查询/带限制条件的查询和表达式查询.sh
@@ -0,0 +1,20 @@
+USE Mall
+Go
+
+SET NOCOUNT ON
+
+---------- retrieving with limited ----------
+-- ********** Begin ********** --
+SELECT prod_name 
+FROM Products 
+WHERE prod_name LIKE '%toy%'
+-- ********** End ********** --
+GO
+
+---------- retrieving with expression ----------
+-- ********** Begin ********** --
+SELECT prod_price, prod_price * 0.8 AS discount_price
+FROM Products
+WHERE prod_price > 3
+-- ********** End ********** --
+GO
\ No newline at end of file