Spring Boot 分库分表策略示例展示

spring:
  datasource:
    dynamic:
      primary: db1
      datasource:
        db1:
          url: jdbc:mysql://localhost:3306/db1
          username: root
          password: password
        db2:
          url: jdbc:mysql://localhost:3306/db2
          username: root
          password: password
        # 添加更多数据源

public class DynamicDataSource extends AbstractRoutingDataSource {
     @Override
     protected Object determineCurrentLookupKey() {
         return DataSourceContextHolder.getDataSourceType();
     }
 }
​
 public class DataSourceContextHolder {
     private static final ThreadLocal<String> contextHolder = new ThreadLocal<>();
​
     public static void setDataSourceType(String dataSourceType) {
         contextHolder.set(dataSourceType);
     }
​
     public static String getDataSourceType() {
         return contextHolder.get();
     }
​
     public static void clearDataSourceType() {
         contextHolder.remove();
     }
 }

public class DataSourceUtil {
     private static final int TOTAL_DATASOURCES = 8;
​
     public static String getDataSourceNameByUserId(Long userId) {
         int index = (int) (userId % TOTAL_DATASOURCES) + 1;
         return "db" + index;
     }
 }

@Configuration
 public class DataSourceConfig {
     @Autowired
     @Qualifier("db1DataSource")
     private DataSource db1DataSource;
​
     @Autowired
     @Qualifier("db2DataSource")
     private DataSource db2DataSource;
​
     // 更多数据源...
​
     @Bean
     public DataSource dataSource() {
         DynamicDataSource dynamicDataSource = new DynamicDataSource();
         Map<Object, Object> targetDataSources = new HashMap<>();
         targetDataSources.put("db1", db1DataSource);
         targetDataSources.put("db2", db2DataSource);
         // 更多数据源...
​
         dynamicDataSource.setTargetDataSources(targetDataSources);
         dynamicDataSource.setDefaultTargetDataSource(db1DataSource);
         return dynamicDataSource;
     }
​
     @Bean
     public PlatformTransactionManager transactionManager() {
         return new DataSourceTransactionManager(dataSource());
     }
 }

public class TableNameUtil {
     public static String getTableNameByMonth(String baseTableName, LocalDate date) {
         String month = date.format(DateTimeFormatter.ofPattern("yyyy_MM"));
         return baseTableName + "_" + month;
     }
​
     public static String getTableNameByIdRange(String baseTableName, Long id) {
         int range = (int) (id / 10000);
         return baseTableName + "_" + range;
     }
​
     public static String getTableNameByUserId(String baseTableName, Long userId) {
         int tableIndex = (int) (userId % 8);
         return baseTableName + "_" + tableIndex;
     }
 }

@Repository
 public class OrderRepository {
     private final JdbcTemplate jdbcTemplate;
​
     public OrderRepository(JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }
​
     public void saveOrder(Order order) {
         String dataSourceName = DataSourceUtil.getDataSourceNameByUserId(order.getUserId());
         DataSourceContextHolder.setDataSourceType(dataSourceName);
​
         String tableName = TableNameUtil.getTableNameByUserId("orders", order.getUserId());
         String sql = "INSERT INTO " + tableName + " (id, order_date, amount) VALUES (?, ?, ?)";
         jdbcTemplate.update(sql, order.getId(), order.getOrderDate(), order.getAmount());
​
         DataSourceContextHolder.clearDataSourceType();
     }
 }