Merge pull request #205239 from saimicrosoft/hsc_app_stacks_extended_latest

HSC - Connection pooling to App Stacks docs

Author: denrea

articles/postgresql/hyperscale/howto-app-stacks-csharp.md

@@ -6,7 +6,7 @@ author: saimicrosoft
 ms.service: postgresql
 ms.subservice: hyperscale-citus
 ms.topic: how-to
-ms.date: 06/20/2022
+ms.date: 07/26/2022
 ---
 
 # C# app to connect and query Hyperscale (Citus)
@@ -38,9 +38,11 @@ To get the database credentials, you can use the **Connection strings** tab in t
 Use the following code to connect and load the data using CREATE TABLE and INSERT INTO SQL statements. The code uses these `NpgsqlCommand` class methods:
 
 * [Open()](https://www.npgsql.org/doc/api/Npgsql.NpgsqlConnection.html#Npgsql_NpgsqlConnection_Open) to establish a connection to Hyperscale (Citus),
-* [CreateCommand()](https://www.npgsql.org/doc/api/Npgsql.NpgsqlConnection.html#Npgsql_NpgsqlConnection_CreateCommand) to set the CommandText property,
+* [CreateCommand()](https://www.npgsql.org/doc/api/Npgsql.NpgsqlConnection.html#Npgsql_NpgsqlConnection_CreateCommand) to set the CommandText property
 * [ExecuteNonQuery()](https://www.npgsql.org/doc/api/Npgsql.NpgsqlCommand.html#Npgsql_NpgsqlCommand_ExecuteNonQuery) to run database commands.
 
+[!INCLUDE[why-connection-pooling](includes/why-connection-pooling.md)]
+
 ```csharp
 using System;
 using Npgsql;
@@ -52,7 +54,7 @@ namespace Driver
         static void Main(string[] args)
         {
             // Replace below argument with connection string from portal.
-            var connStr = new NpgsqlConnectionStringBuilder("Server = <host> Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require;");
+            var connStr = new NpgsqlConnectionStringBuilder("Server = <host> Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require; Pooling = true; Minimum Pool Size=0; Maximum Pool Size =50 ");
 
             connStr.TrustServerCertificate = true;
 
@@ -113,7 +115,7 @@ namespace Driver
         static void Main(string[] args)
         {
             // Replace below argument with connection string from portal.
-            var connStr = new NpgsqlConnectionStringBuilder("Server = <host>; Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require;");
+            var connStr = new NpgsqlConnectionStringBuilder("Server = <host> Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require; Pooling = true; Minimum Pool Size=0; Maximum Pool Size =50");
 
             connStr.TrustServerCertificate = true;
 
@@ -155,11 +157,11 @@ namespace Driver
         static void Main(string[] args)
         {
             // Replace below argument with connection string from portal.
-            var connStr = new NpgsqlConnectionStringBuilder("Server = <host>; Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require;");
+            var connStr = new NpgsqlConnectionStringBuilder("Server = <host> Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require; Pooling = true; Minimum Pool Size=0; Maximum Pool Size =50 ");
 
             connStr.TrustServerCertificate = true;
 
-            using (var conn = new NpgsqlConnection(connString))
+            using (var conn = new NpgsqlConnection(connStr))
             {
                 Console.Out.WriteLine("Opening connection");
                 conn.Open();
@@ -203,7 +205,7 @@ namespace Driver
         static void Main(string[] args)
         {
             // Replace below argument with connection string from portal.
-            var connStr = new NpgsqlConnectionStringBuilder("Server = <host>; Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require;");
+            var connStr = new NpgsqlConnectionStringBuilder("Server = <host> Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require; Pooling = true; Minimum Pool Size=0; Maximum Pool Size =50 ");
 
             connStr.TrustServerCertificate = true;
 
@@ -241,7 +243,7 @@ namespace Driver
         static void Main(string[] args)
         {
             // Replace below argument with connection string from portal.
-            var connStr = new NpgsqlConnectionStringBuilder("Server = <host>; Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require;");
+            var connStr = new NpgsqlConnectionStringBuilder("Server = <host> Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require; Pooling = true; Minimum Pool Size=0; Maximum Pool Size =50 ");
 
             connStr.TrustServerCertificate = true;
 
@@ -285,7 +287,7 @@ public class csvtotable
         String sFromFilePath = "C:\\Users\\Documents\\pharmacies.csv";
 
         // Replace below argument with connection string from portal.
-        var connStr = new NpgsqlConnectionStringBuilder("Server = <host>; Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require;");
+        var connStr = new NpgsqlConnectionStringBuilder("Server = <host> Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require; Pooling = true; Minimum Pool Size=0; Maximum Pool Size =50 ");
 
         connStr.TrustServerCertificate = true;
 
@@ -325,7 +327,7 @@ namespace Driver
         {
 
              // Replace below argument with connection string from portal.
-            var connStr = new NpgsqlConnectionStringBuilder("Server = <host>; Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require;");
+            var connStr = new NpgsqlConnectionStringBuilder("Server = <host> Database = citus; Port = 5432; User Id = citus; Password = {your password}; Ssl Mode = Require; Pooling = true; Minimum Pool Size=0; Maximum Pool Size =50 ");
 
             connStr.TrustServerCertificate = true;
 

articles/postgresql/hyperscale/howto-app-stacks-java.md

@@ -6,7 +6,7 @@ author: saimicrosoft
 ms.service: postgresql
 ms.subservice: hyperscale-citus
 ms.topic: how-to
-ms.date: 06/20/2022
+ms.date: 07/26/2022
 ---
 
 # Java app to connect and query Hyperscale (Citus)
@@ -71,6 +71,12 @@ Using your favorite IDE, create a new Java project with groupId **test** and art
       <artifactId>postgresql</artifactId>
       <version>42.2.12</version>
     </dependency>
+    <!-- https://mvnrepository.com/artifact/com.zaxxer/HikariCP -->
+    <dependency>
+      <groupId>com.zaxxer</groupId>
+      <artifactId>HikariCP</artifactId>
+      <version>5.0.0</version>
+    </dependency>
     <dependency>
       <groupId>org.junit.jupiter</groupId>
       <artifactId>junit-jupiter-params</artifactId>
@@ -101,6 +107,7 @@ This file configures [Apache Maven](https://maven.apache.org/) to use:
 Create a `src/main/resources/application.properties` file, and add:
 
 ``` properties
+driver.class.name=org.postgresql.Driver
 url=jdbc:postgresql://<host>:5432/citus?ssl=true&sslmode=require
 user=citus
 password=<password>
@@ -142,6 +149,61 @@ select create_distributed_table('public.pharmacy','pharmacy_id');
 
 Next, add the Java code that will use JDBC to store and retrieve data from your Hyperscale (Citus) server group.
 
+#### Connection Pooling Setup
+
+Using the code below, create a `DButil.java` file, which contains the `DButil`
+class. The `DBUtil` class sets up a connection pool to PostgreSQL using
+[HikariCP](https://github.com/brettwooldridge/HikariCP). In the example
+application, we'll be using this class to connect to PostgreSQL and start
+querying.
+
+[!INCLUDE[why-connection-pooling](includes/why-connection-pooling.md)]
+
+```java
+//DButil.java
+package test.crud;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.sql.SQLException;
+import java.util.Properties;
+
+import javax.sql.DataSource;
+
+import com.zaxxer.hikari.HikariDataSource;
+
+public class DButil {
+    private static final String DB_USERNAME = "db.username";
+    private static final String DB_PASSWORD = "db.password";
+    private static final String DB_URL = "db.url";
+    private static final String DB_DRIVER_CLASS = "driver.class.name";
+    private static Properties properties =  null;
+    private static HikariDataSource datasource;
+
+    static {
+        try {
+            properties = new Properties();
+            properties.load(new FileInputStream("src/main/java/application.properties"));
+
+            datasource = new HikariDataSource();
+            datasource.setDriverClassName(properties.getProperty(DB_DRIVER_CLASS ));
+            datasource.setJdbcUrl(properties.getProperty(DB_URL));
+            datasource.setUsername(properties.getProperty(DB_USERNAME));
+            datasource.setPassword(properties.getProperty(DB_PASSWORD));
+            datasource.setMinimumIdle(100);
+            datasource.setMaximumPoolSize(1000000000);
+            datasource.setAutoCommit(false);
+            datasource.setLoginTimeout(3);
+        } catch (IOException | SQLException  e) {
+            e.printStackTrace();
+        }
+    }
+    public static DataSource getDataSource() {
+        return datasource;
+    }
+}
+```
+
 Create a `src/main/java/DemoApplication.java` file that contains:
 
 ``` java
@@ -168,11 +230,9 @@ public class DemoApplication {
     }
     public static void main(String[] args)throws Exception
     {
-        log.info("Loading application properties");
-        Properties properties = new Properties();
-        properties.load(DemoApplication.class.getClassLoader().getResourceAsStream("application.properties"));
         log.info("Connecting to the database");
-        Connection connection = DriverManager.getConnection(properties.getProperty("url"), properties);
+        Connection connection = DButil.getDataSource().getConnection();
+        System.out.println("The Connection Object is of Class: " + connection.getClass());
         log.info("Database connection test: " + connection.getCatalog());
         log.info("Creating table");
         log.info("Creating index");
@@ -272,12 +332,12 @@ public class Pharmacy {
     }
     @Override
     public String toString() {
-        return "TPharmacy{"
-               "pharmacy_id=" + pharmacy_id
-               ", pharmacy_name='" + pharmacy_name + '\''
-               ", city='" + city + '\''
-                   ", state='" + state + '\''
-                   ", zip_code='" + zip_code + '\''
+        return "TPharmacy{" +
+               "pharmacy_id=" + pharmacy_id +
+               ", pharmacy_name='" + pharmacy_name + '\'' +
+               ", city='" + city + '\'' +
+               ", state='" + state + '\'' +
+               ", zip_code='" + zip_code + '\'' +
                '}';
     }
 }
@@ -472,14 +532,17 @@ The following code is an example for copying data from a CSV file to a database
 It requires the file [pharmacies.csv](https://download.microsoft.com/download/d/8/d/d8d5673e-7cbf-4e13-b3e9-047b05fc1d46/pharmacies.csv).
 
 ```java
-public static long copyFromFile(Connection connection, String filePath, String tableName)
-    throws SQLException, IOException
-{
+public static long
+copyFromFile(Connection connection, String filePath, String tableName)
+throws SQLException, IOException {
     long count = 0;
     FileInputStream fileInputStream = null;
 
     try {
-        CopyManager copyManager = new CopyManager((BaseConnection) connection);
+        Connection unwrap = connection.unwrap(Connection.class);
+        BaseConnection  connSec = (BaseConnection) unwrap;
+
+        CopyManager copyManager = new CopyManager((BaseConnection) connSec);
         fileInputStream = new FileInputStream(filePath);
         count = copyManager.copyIn("COPY " + tableName + " FROM STDIN delimiter ',' csv", fileInputStream);
     } finally {
@@ -531,16 +594,20 @@ The following code is an example for copying in-memory data to table.
 ```java
 private static void inMemory(Connection connection) throws SQLException,IOException {
     log.info("Copying in-memory data into table");
-    String[] input = {"5000,Target,Sunnyvale,California,94001"};
+    String[] input = {"0,Target,Sunnyvale,California,94001"};
+
+    Connection unwrap = connection.unwrap(Connection.class);
+    BaseConnection  connSec = (BaseConnection) unwrap;
 
-    CopyManager copyManager = new CopyManager((BaseConnection) connection);
-    String copyCommand = "COPY pharmacy FROM STDIN with csv " ;
+    CopyManager copyManager = new CopyManager((BaseConnection) connSec);
+    String copyCommand = "COPY pharmacy FROM STDIN with csv";
 
     for (String var : input)
     {
         Reader reader = new StringReader(var);
         copyManager.copyIn(copyCommand, reader);
     }
+
     copyManager.copyIn(copyCommand);
 }
 ```