從數(shù)據(jù)庫中導(dǎo)出源數(shù)據(jù)

源數(shù)據(jù)可以由用戶自行生成，也可以從數(shù)據(jù)庫中導(dǎo)出，本文以mysql -e命令的方式導(dǎo)出進(jìn)行示例，具體方法如下：

mysql -h ip  -P port -u usr -pPassword db_name -N -e "SELECT id,k,c,pad FROM sourcedb;" >/home/data_1000w.txt
## 原始數(shù)據(jù)以制表符分隔，數(shù)據(jù)格式：188092293    27267211    59775766593-64673028018-...-09474402685    01705051424-...-54211554755

mysql -h ip  -P port -u usr -pPassword db_name -N -e "SELECT id,k,c,pad FROM sourcedb;" | sed 's/\t/,/g' >/home/data_1000w.csv
## csv文件格式以逗號(hào)分隔，數(shù)據(jù)格式：188092293,27267211,59775766593-64673028018-...-09474402685,01705051424-...-54211554755

推薦將字符串進(jìn)行處理，轉(zhuǎn)變成csv文件格式，方便后續(xù)程序讀取數(shù)據(jù)。

在PolarDB-X中創(chuàng)建目標(biāo)表

源數(shù)據(jù)不包括建表語句，需要手動(dòng)在PolarDB-X目標(biāo)數(shù)據(jù)庫上創(chuàng)建表，示例如下：

CREATE TABLE `targetdb` (
    `id` int(11) NOT NULL,
    `k` int(11) NOT NULL DEFAULT '0',
    `c` char(120) NOT NULL DEFAULT '',
    `pad` char(60) NOT NULL DEFAULT '',
    PRIMARY KEY (`id`),
    KEY `k_1` (`k`)
) ENGINE = InnoDB DEFAULT CHARSET = utf8mb4 dbpartition by hash(`id`);

使用程序?qū)霐?shù)據(jù)到PolarDB-X

您可以自行編寫程序，連接PolarDB-X，然后讀取本地?cái)?shù)據(jù)，通過Batch Insert語句導(dǎo)入到PolarDB-X中。

下面是一個(gè)簡(jiǎn)單的Java程序示例：

// 需要mysql-connector-java.jar, 詳情界面：https://mvnrepository.com/artifact/mysql/mysql-connector-java
// 下載鏈接：https://repo1.maven.org/maven2/mysql/mysql-connector-java/8.0.20/mysql-connector-java-8.0.20.jar
// 注：不同版本的mysql-connector-java.jar，可能Class.forName("com.mysql.cj.jdbc.Driver")類路徑不同
// 編譯 javac LoadData.java
// 運(yùn)行 java -cp .:mysql-connector-java-8.0.20.jar LoadData

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;

public class LoadData {
    public static void main(String[] args) throws IOException, ClassNotFoundException, SQLException {
        File dataFile = new File("/home/data_1000w.csv");
        String sql = "insert into targetdb(id, k, c, pad) values(?, ?, ?, ?)";
        int batchSize = 1000;
        try (
            Connection connection = getConnection("ip", 3306, "db", "usr", "password");
            BufferedReader br = new BufferedReader(new FileReader(dataFile))) {
            String line;
            PreparedStatement st = connection.prepareStatement(sql);
            long startTime = System.currentTimeMillis();
            int batchCount = 0;

            while ((line = br.readLine()) != null) {
                String[] data = line.split(",");
                st.setInt(1, Integer.valueOf(data[0]));
                st.setInt(2, Integer.valueOf(data[1]));
                st.setObject(3, data[2]);
                st.setObject(4, data[3]);

                st.addBatch();
                if (++batchCount % batchSize == 0) {
                    st.executeBatch();
                    System.out.println(String.format("insert %d records", batchCount));
                }
            }
            if (batchCount % batchSize != 0) {
                st.executeBatch();
            }
            long cost = System.currentTimeMillis() - startTime;
            System.out.println(String.format("Take %d second，insert %d records, tps %d", cost/1000, batchCount, batchCount/(cost/1000)));
        }
    }
    /**
     * 獲取數(shù)據(jù)庫連接
     *
     * @param host     數(shù)據(jù)庫地址
     * @param port     端口
     * @param database 數(shù)據(jù)庫名稱
     * @param username 用戶名
     * @param password 密碼
     * @return
     * @throws ClassNotFoundException
     * @throws SQLException
     */
    private static Connection getConnection(String host, int port, String database, String username, String password)
        throws ClassNotFoundException, SQLException {
        Class.forName("com.mysql.cj.jdbc.Driver");
        String url = String.format(
            "jdbc:mysql://%s:%d/%s?autoReconnect=true&socketTimeout=600000&rewriteBatchedStatements=true", host, port,
            database);
        Connection con = DriverManager.getConnection(url, username, password);
        return con;
    }
}

您可以根據(jù)實(shí)際應(yīng)用場(chǎng)景編寫程序，設(shè)置合適的batch size和多線程導(dǎo)入，來提高導(dǎo)入的性能。