Merge branch 'jdbc-advanced' into development

完成JDBC进阶课程的代码及介绍.
osxcn · Aug 20, 2017 · 126565f · 126565f
2 parents 001d051 + 010632c
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diff --git a/README.md b/README.md
@@ -30,6 +30,10 @@
 		* [1.6.2 常用JDBC URL](#162-常用jdbc-url)
 	* [1.7 构建步骤](#17-构建步骤)
 	* [1.8 JDBC高级功能](#18-jdbc高级功能)
+		* [1.8.1 游标](#181-游标)
+		* [1.8.2 流方式](#182-流方式)
+		* [1.8.3 批处理](#183-批处理)
+		* [1.8.4 字符集设置](#184-字符集设置)
 * [2. 数据库连接池](#2-数据库连接池)
 	* []()
 * [3. SQL注入与防范](#3-sql注入与防范)
@@ -151,6 +155,8 @@ jdbc:microsoft:sqlserver://<ip>:<port>;DatabaseName=database
 4. 获取执行结果
 5. 清理环境
 
+[构建实例：JDBC基础-HelloJDBC](/src/main/java/com/micro/profession/jdbc/practice/HelloJDBC.java)
+
 ### 1.8 JDBC高级功能
 #### 1.8.1 游标
 游标提供一种客户端能够部分读取服务器端结果集的功能支持，允许分批读取SQL查询的结果。
@@ -164,12 +170,49 @@ jdbc:mysql://&lt;ip&gt;:&lt;port&gt;/&lt;database&gt;<a href="#db_url"><strong>?
 &emsp;&emsp;`PreparedStatement`继承自`Statement`接口，可以使用`PreparedStatement`接口来替代`Statement`接口，`PreparedStatement`接口相比`Statement`接口要求程序员在生成`PreparedStatement`的时候就要传入SQL语句，这个SQL语句是一个`参数格式化`的SQL，也就是说，SQL的`WHERE`过滤条件的参数都是通过`?`的形式来表示的，后续是通过`PreparedStatement`的`setString`和`setInt`方法来设置这些参数，然后进行执行。  
 &emsp;&emsp;`PreparedStatement`有个`setFetchSize`接口，这个接口可以实现游标的功能。通过`setFetchSize`，就可以设置客户端JDBC每次从服务器端取回的记录的数量。
 
-#### 1.8.2 
+应用场景：查询时返回记录过多。
+
+[构建实例：JDBC进阶-游标-HelloJDBC_cursor](/src/main/java/com/micro/profession/jdbc/practice/HelloJDBC_cursor.java)
+
+#### 1.8.2 流方式
+流方式就是将大字段的内容以二进制的方式按照区间进行划分，划分为多个区间，每次读取一个区间中的内容，在处理结束后再读取下一个区间。
+
+应用场景：读取大字段数据。
+
+[构建实例：JDBC进阶-流方式-LiuFang](/src/main/java/com/micro/profession/jdbc/practice/LiuFang.java)
 
-#### 1.8.3 
+#### 1.8.3 批处理
+批处理就是通过发送一次SQL可以插入多条数据，即将多条SQL一次性进行发送。
 
-#### 1.8.4 
+批处理使用涉及到`Statement`的三个函数：
+* addBatch()		把SQL打包成一个执行单元(Batch)
+* executeBatch()	执行SQL
+* clearBatch()		清空Batch中的SQL语句，准备下次执行
 
+注：`PreparedStatement`同样可以使用这三个函数
+
+应用场景：大量数据插入操作。
+
+[构建实例：JDBC进阶-批处理-BatchTest](/src/main/java/com/micro/profession/jdbc/practice/BatchTest.java)
+
+#### 1.8.4 字符集设置
+1. 获取数据库编码设置
+```mysql
+show variables like '%character%';
+```
+2. 编码级别
+* 实例级别：character_set_server
+* 数据库级别：character_set_database
+* 表级别：DEFAULT CHARSET=utf8
+* 列级别：CHARACTER SET utf8
+`
+编码级别优先顺序：Server < Database < Table < Column
+`
+3. JDBC设置
+
+`DB_URL` = `DB_URL` + `characterEncoding=utf8`
+
+注：为了保证中文不出错，无论是数据库的还是JDBC的，建议设置为`utf8`
 
 ## 2. 数据库连接池
 

diff --git a/file/write.txt b/file/write.txt
@@ -0,0 +1 @@
+testread
diff --git a/sql/1. jdbc基础/cloud_study_jdbc-basic.sql b/sql/1. jdbc基础/cloud_study_jdbc-basic.sql
@@ -1,37 +1,37 @@
-/*
- Navicat Premium Data Transfer
-
- Source Server         : local
- Source Server Type    : MySQL
- Source Server Version : 50635
- Source Host           : localhost:3306
- Source Schema         : cloud_study
-
- Target Server Type    : MySQL
- Target Server Version : 50635
- File Encoding         : 65001
-
- Date: 15/08/2017 21:07:48
-*/
-
-SET NAMES utf8mb4;
-SET FOREIGN_KEY_CHECKS = 0;
-
--- ----------------------------
--- Table structure for user
--- ----------------------------
-DROP TABLE IF EXISTS `user`;
-CREATE TABLE `user`  (
-  `id` int(11) NOT NULL AUTO_INCREMENT,
-  `userName` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
-  PRIMARY KEY (`id`) USING BTREE
-) ENGINE = InnoDB AUTO_INCREMENT = 4 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Compact;
-
--- ----------------------------
--- Records of user
--- ----------------------------
-INSERT INTO `user` VALUES (1, 'ZhangSan');
-INSERT INTO `user` VALUES (2, 'LiSi');
-INSERT INTO `user` VALUES (3, 'ZhaoWu');
-
-SET FOREIGN_KEY_CHECKS = 1;
+/*
+ Navicat Premium Data Transfer
+
+ Source Server         : local
+ Source Server Type    : MySQL
+ Source Server Version : 50635
+ Source Host           : localhost:3306
+ Source Schema         : cloud_study
+
+ Target Server Type    : MySQL
+ Target Server Version : 50635
+ File Encoding         : 65001
+
+ Date: 15/08/2017 21:07:48
+*/
+
+SET NAMES utf8mb4;
+SET FOREIGN_KEY_CHECKS = 0;
+
+-- ----------------------------
+-- Table structure for user
+-- ----------------------------
+DROP TABLE IF EXISTS `user`;
+CREATE TABLE `user`  (
+  `id` int(11) NOT NULL AUTO_INCREMENT,
+  `userName` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
+  PRIMARY KEY (`id`) USING BTREE
+) ENGINE = InnoDB AUTO_INCREMENT = 4 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Compact;
+
+-- ----------------------------
+-- Records of user
+-- ----------------------------
+INSERT INTO `user` VALUES (1, 'ZhangSan');
+INSERT INTO `user` VALUES (2, 'LiSi');
+INSERT INTO `user` VALUES (3, 'ZhaoWu');
+
+SET FOREIGN_KEY_CHECKS = 1;
diff --git a/sql/2. jdbc进阶/cloud_study_liufang.sql b/sql/2. jdbc进阶/cloud_study_liufang.sql
@@ -0,0 +1,51 @@
+/*
+ Navicat Premium Data Transfer
+
+ Source Server         : local
+ Source Server Type    : MySQL
+ Source Server Version : 50635
+ Source Host           : localhost:3306
+ Source Schema         : cloud_study
+
+ Target Server Type    : MySQL
+ Target Server Version : 50635
+ File Encoding         : 65001
+
+ Date: 20/08/2017 22:01:32
+*/
+
+SET NAMES utf8mb4;
+SET FOREIGN_KEY_CHECKS = 0;
+
+-- ----------------------------
+-- Table structure for user
+-- ----------------------------
+DROP TABLE IF EXISTS `user`;
+CREATE TABLE `user`  (
+  `id` int(11) NOT NULL AUTO_INCREMENT,
+  `userName` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
+  `corp` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
+  PRIMARY KEY (`id`) USING BTREE
+) ENGINE = InnoDB AUTO_INCREMENT = 2 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Compact;
+
+-- ----------------------------
+-- Records of user
+-- ----------------------------
+INSERT INTO `user` VALUES (1, 'ZhangSan', 'Netease');
+
+-- ----------------------------
+-- Table structure for user_note
+-- ----------------------------
+DROP TABLE IF EXISTS `user_note`;
+CREATE TABLE `user_note`  (
+  `id` int(11) NOT NULL AUTO_INCREMENT,
+  `blog` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
+  PRIMARY KEY (`id`) USING BTREE
+) ENGINE = InnoDB AUTO_INCREMENT = 2 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Compact;
+
+-- ----------------------------
+-- Records of user_note
+-- ----------------------------
+INSERT INTO `user_note` VALUES (1, 'testread');
+
+SET FOREIGN_KEY_CHECKS = 1;
diff --git a/src/main/java/com/micro/profession/jdbc/practice/BatchTest.java b/src/main/java/com/micro/profession/jdbc/practice/BatchTest.java
@@ -0,0 +1,60 @@
+package com.micro.profession.jdbc.practice;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.HashSet;
+import java.util.Set;
+
+public class BatchTest {
+
+	static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
+	static String DB_URL = "jdbc:mysql://localhost/cloud_study";
+	static final String USER = "root";
+	static final String PASSWORD = "root";
+
+	public static void insertUsers(Set<String> users) 
+			throws ClassNotFoundException {
+		Connection conn = null;
+		Statement stmt = null;
+
+		//1. 加载数据库驱动
+		Class.forName(JDBC_DRIVER);
+		//2. 建立数据库连接
+		try {
+			// 获得数据库连接
+			conn = DriverManager.getConnection(DB_URL, USER, PASSWORD);
+			//3. 执行SQL语句
+			stmt = conn.createStatement();
+			for(String user : users) {
+				stmt.addBatch("insert into user(userName) values ('" + user
+						+ "')");
+			}
+			stmt.executeBatch();
+			stmt.clearBatch();
+		} catch (SQLException e) {
+			// 异常处理
+			e.printStackTrace();
+		} finally {
+			//5. 清理环境
+			try {
+				if(conn != null)
+					conn.close();
+				if(stmt != null)
+					stmt.close();
+			} catch (SQLException e) {
+				// ignore
+			}
+		}
+	}
+
+	public static void main(String[] args) throws ClassNotFoundException {
+		Set<String> users = new HashSet<String>();
+		users.add("GuoYi");
+		users.add("ZhangSi");
+		users.add("LiSan");
+		insertUsers(users);
+	}
+
+}
diff --git a/src/main/java/com/micro/profession/jdbc/practice/HelloJDBC.java b/src/main/java/com/micro/profession/jdbc/practice/HelloJDBC.java
@@ -1,56 +1,56 @@
-package com.micro.profession.jdbc.practice;
-
-import java.sql.Connection;
-import java.sql.DriverManager;
-import java.sql.ResultSet;
-import java.sql.SQLException;
-import java.sql.Statement;
-
-public class HelloJDBC {
-
-	static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
-	static String DB_URL = "jdbc:mysql://localhost/cloud_study";
-	static final String USER = "root";
-	static final String PASSWORD = "root";
-
-	public static void helloword() throws ClassNotFoundException {
-		Connection conn = null;
-		Statement stmt = null;
-		ResultSet rs = null;
-
-		//1. 加载数据库驱动
-		Class.forName(JDBC_DRIVER);
-		//2. 建立数据库连接
-		try {
-			// 获得数据库连接
-			conn = DriverManager.getConnection(DB_URL, USER, PASSWORD);
-			//3. 执行SQL语句
-			stmt = conn.createStatement();
-			rs = stmt.executeQuery("select userName from user");
-			//4. 获取执行结果
-			while(rs.next()) {
-				System.out.println("hello " + rs.getString("userName"));
-			}
-		} catch (SQLException e) {
-			// 异常处理
-			e.printStackTrace();
-		} finally {
-			//5. 清理环境
-			try {
-				if(conn != null)
-					conn.close();
-				if(stmt != null)
-					stmt.close();
-				if(rs != null)
-					rs.close();
-			} catch (SQLException e) {
-				// ignore
-			}
-		}
-	}
-
-	public static void main(String[] args) throws ClassNotFoundException {
-		helloword();
-	}
-
-}
+package com.micro.profession.jdbc.practice;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+public class HelloJDBC {
+
+	static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
+	static String DB_URL = "jdbc:mysql://localhost/cloud_study";
+	static final String USER = "root";
+	static final String PASSWORD = "root";
+
+	public static void helloword() throws ClassNotFoundException {
+		Connection conn = null;
+		Statement stmt = null;
+		ResultSet rs = null;
+
+		//1. 加载数据库驱动
+		Class.forName(JDBC_DRIVER);
+		//2. 建立数据库连接
+		try {
+			// 获得数据库连接
+			conn = DriverManager.getConnection(DB_URL, USER, PASSWORD);
+			//3. 执行SQL语句
+			stmt = conn.createStatement();
+			rs = stmt.executeQuery("select userName from user");
+			//4. 获取执行结果
+			while(rs.next()) {
+				System.out.println("hello " + rs.getString("userName"));
+			}
+		} catch (SQLException e) {
+			// 异常处理
+			e.printStackTrace();
+		} finally {
+			//5. 清理环境
+			try {
+				if(conn != null)
+					conn.close();
+				if(stmt != null)
+					stmt.close();
+				if(rs != null)
+					rs.close();
+			} catch (SQLException e) {
+				// ignore
+			}
+		}
+	}
+
+	public static void main(String[] args) throws ClassNotFoundException {
+		helloword();
+	}
+
+}