diff --git a/tests/examples/JDBC/JDBCDemo/pom.xml b/tests/examples/JDBC/JDBCDemo/pom.xml
index 0fa7aac48b0e36a7f1faecb78c9c2e323bbe0ea2..167e7e37ae410dd865aa2e08c7f885961f9ddadd 100644
--- a/tests/examples/JDBC/JDBCDemo/pom.xml
+++ b/tests/examples/JDBC/JDBCDemo/pom.xml
@@ -13,7 +13,7 @@
         <dependency>
             <groupId>com.taosdata.jdbc</groupId>
             <artifactId>taos-jdbcdriver</artifactId>
-            <version>2.0.14</version>
+            <version>2.0.20</version>
         </dependency>
     </dependencies>
 
diff --git a/tests/examples/JDBC/taosdemo/pom.xml b/tests/examples/JDBC/taosdemo/pom.xml
index 278212e75d67130d6d6d318348c928684e849481..22c2f3b63e82a3a2cdcc3093c3c43b98ab534a4b 100644
--- a/tests/examples/JDBC/taosdemo/pom.xml
+++ b/tests/examples/JDBC/taosdemo/pom.xml
@@ -67,7 +67,7 @@
         <dependency>
             <groupId>com.taosdata.jdbc</groupId>
             <artifactId>taos-jdbcdriver</artifactId>
-            <version>2.0.19</version>
+            <version>2.0.20</version>
             <!--  <scope>system</scope>-->
             <!--  <systemPath>${project.basedir}/src/main/resources/lib/taos-jdbcdriver-2.0.15-dist.jar</systemPath>-->
         </dependency>
diff --git a/tests/examples/JDBC/taosdemo/src/main/java/com/taosdata/taosdemo/TaosDemoApplication.java b/tests/examples/JDBC/taosdemo/src/main/java/com/taosdata/taosdemo/TaosDemoApplication.java
index 69e2606a79041c270fca7d7af1abb33c666d1fad..19f47e13d6112b8e638fc24e5d8f7f257602c0ae 100644
--- a/tests/examples/JDBC/taosdemo/src/main/java/com/taosdata/taosdemo/TaosDemoApplication.java
+++ b/tests/examples/JDBC/taosdemo/src/main/java/com/taosdata/taosdemo/TaosDemoApplication.java
@@ -35,7 +35,7 @@ public class TaosDemoApplication {
         final DatabaseService databaseService = new DatabaseService(dataSource);
         final SuperTableService superTableService = new SuperTableService(dataSource);
         final SubTableService subTableService = new SubTableService(dataSource);
-        final QueryService queryService = new QueryService(dataSource);
+
         // 创建数据库
         long start = System.currentTimeMillis();
         Map<String, String> databaseParam = new HashMap<>();
diff --git a/tests/examples/JDBC/taosdemo/src/main/resources/application.properties b/tests/examples/JDBC/taosdemo/src/main/resources/application.properties
index 6fd38f1762e6879422cf26fe2dc617caeb5e297c..488185196f1d2325fd9896d30068cbb202180a3f 100644
--- a/tests/examples/JDBC/taosdemo/src/main/resources/application.properties
+++ b/tests/examples/JDBC/taosdemo/src/main/resources/application.properties
@@ -1,5 +1,5 @@
 jdbc.driver=com.taosdata.jdbc.rs.RestfulDriver
 #jdbc.driver=com.taosdata.jdbc.TSDBDriver
-hikari.maximum-pool-size=1
-hikari.minimum-idle=1
+hikari.maximum-pool-size=20
+hikari.minimum-idle=20
 hikari.max-lifetime=0
\ No newline at end of file