垂直分表: 将一张宽表(字段很多的表), 按照字段的访问频次进行拆分,就是按照表单结构进行 拆。
垂直分库: 根据不同的业务,将表进行分类, 拆分到不同的数据库. 这些库可以部署在不同的服 务器,分摊访问压力.
水平分库: 将一张表的数据 ( 按照数据行) 分到多个不同的数据库.每个库的表结构相同
水平分表: 将一张表的数据 ( 按照数据行) , 分配到同一个数据库的多张表中,每个表都只有一部 分数据.
接下来阿粉就实战使用SpringBoot和Mysql 来说实现分库分表,直接先从Sharding 开始,毕竟是jar包的方式,相对来说比较简单。
我们首先先从分表来开始我们使用Sharding-JDBC的操作。
第一步创建数据库及其对应的相同的两张表结构的表
我们先从我们的mysql上创建我们的数据库,直接起名叫做order库
然后我们分别创建两个表,分别是order_1 和order2。
这两张表是订单表拆分后的表,我们通过Sharding-Jdbc向订单表插入数据,按照一定的分片规则,主键 为偶数的落入order_1表 ,为奇数的落入order_2表, 再通过Sharding-Jdbc 进行查询.
DROP TABLE IF EXISTS order_1;
CREATE TABLE order_1 (
order_id BIGINT(20) PRIMARY KEY AUTO_INCREMENT ,
user_id INT(11) ,
product_name VARCHAR(128),
COUNT INT(11)
);
DROP TABLE IF EXISTS order_2;
CREATE TABLE order_2 (
order_id BIGINT(20) PRIMARY KEY AUTO_INCREMENT ,
user_id INT(11) ,
product_name VARCHAR(128),
COUNT INT(11)
);
第二步
创建一个SpringBoot的项目,然后配置Sharding的依赖
依赖如下:
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.apache.shardingsphere</groupId>
<artifactId>sharding-jdbc-spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-typehandlers-jsr310</artifactId>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.xml.bind/jaxb-api -->
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>2.3.0-b170201.1204</version>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.activation/activation -->
<dependency>
<groupId>javax.activation</groupId>
<artifactId>activation</artifactId>
<version>1.1</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.glassfish.jaxb/jaxb-runtime -->
<dependency>
<groupId>org.glassfish.jaxb</groupId>
<artifactId>jaxb-runtime</artifactId>
<version>2.3.0-b170127.1453</version>
</dependency>
第三步
第三步也是我们这里相对来说比较重要的一步,那就是配置分片规则,因为这里的分表是直接把数据进行水平拆分成到2个表中,所以属于水平切分数据表的操作,配置如下:
spring:
application:
name: sharding-jdbc-simple
http:
encoding:
enabled: true
charset: UTF-8
force: true
main:
allow-bean-definition-overriding: true
shardingsphere:
datasource:
names: db1
db1:
type: com.alibaba.druid.pool.DruidDataSource
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://127.0.0.1:3306/order?characterEncoding=UTF-8&useSSL=false
username: root
password: 123456
sharding:
tables:
order:
actual-data-nodes: db1.pay_order_$->{1..2}
key-generator:
column: order_id
type: SNOWFLAKE
table-strategy:
inline:
sharding-column: order_id
algorithm-expression: pay_order_$->{order_id % 2 + 1}
props:
sql:
show: true
server:
servlet:
context-path: /sharding-jdbc
mybatis:
configuration:
map-underscore-to-camel-case: true
上面的配置,就是完整的配置Sharding-JDBC配置了,其中还包括了 Mybatis 的一个配置,以及SQL日志打印。
接下来我们直接写一个Junit测试,然后在我们的数据库中直接插入数据看一下,偶数订单在表1中,基数订单在表2中。
Junit测试
@Mapper
@Component
public interface OrderDao {
/**
* 新增订单
* */
@Insert("INSERT INTO order(user_id,product_name,COUNT) VALUES(#{user_id},#{product_name},#{count})")
int insertOrder(@Param("user_id") int user_id,@Param("product_name") String product_name,@Param("count") int count);
}
//测试
public class OrderTest {
@Autowired
OrderDao orderDao;
@Test
public void testInsertOrder(){
for (int i = 0; i < 10; i++) {
orderDao.insertOrder(100+i,"大冰箱"+i,10);
}
}
}
当我们执行完毕的时候,我们去数据库里面去看一下这个数据是不是分开保存到两个不同表,在看之前先看看打印的sql日志。
SQLStatement: InsertStatement(super=DMLStatement(super=AbstractSQLStatement(type=DML, tables=Tables(tables=[Table(name=order, alias=Optional.absent())]), routeConditions=Conditions(orCondition=OrCondition(andConditions=[AndCondition(conditions=[])])), encryptConditions=Conditions(orCondition=OrCondition(andConditions=[])), sqlTokens=[TableToken(tableName=order, quoteCharacter=NONE, schemaNameLength=0), SQLToken(startIndex=17)], parametersIndex=3, logicSQL=INSERT INTO order(user_id,product_name,COUNT) VALUES(?,?,?)), deleteStatement=false, updateTableAlias={}, updateColumnValues={}, whereStartIndex=0, whereStopIndex=0, whereParameterStartIndex=0, whereParameterEndIndex=0), columnNames=[user_id, product_name, COUNT], values=[InsertValue(columnValues=[org.apache.shardingsphere.core.parse.old.parser.expression.SQLPlaceholderExpression@d611f1c, org.apache.shardingsphere.core.parse.old.parser.expression.SQLPlaceholderExpression@4f2d014a, org.apache.shardingsphere.core.parse.old.parser.expression.SQLPlaceholderExpression@51fc862e])])
2022-06-13 13:47:59.923 INFO 7384 --- [ main] ShardingSphere-SQL : Actual SQL: db1 ::: INSERT INTO order_1 (user_id, product_name, COUNT, order_id) VALUES (?, ?, ?, ?) ::: [107, 大冰箱7, 10, 743103497175564288]
2022-06-13 13:47:59.976 INFO 7384 --- [ main] ShardingSphere-SQL : Rule Type: sharding
2022-06-13 13:47:59.976 INFO 7384 --- [ main] ShardingSphere-SQL : Logic SQL: INSERT INTO order(user_id,product_name,COUNT) VALUES(?,?,?)
2022-06-13 13:47:59.976 INFO 7384 --- [ main] ShardingSphere-SQL : SQLStatement: InsertStatement(super=DMLStatement(super=AbstractSQLStatement(type=DML, tables=Tables(tables=[Table(name=order, alias=Optional.absent())]), routeConditions=Conditions(orCondition=OrCondition(andConditions=[AndCondition(conditions=[])])), encryptConditions=Conditions(orCondition=OrCondition(andConditions=[])), sqlTokens=[TableToken(tableName=order, quoteCharacter=NONE, schemaNameLength=0), SQLToken(startIndex=17)], parametersIndex=3, logicSQL=INSERT INTO order(user_id,product_name,COUNT) VALUES(?,?,?)), deleteStatement=false, updateTableAlias={}, updateColumnValues={}, whereStartIndex=0, whereStopIndex=0, whereParameterStartIndex=0, whereParameterEndIndex=0), columnNames=[user_id, product_name, COUNT], values=[InsertValue(columnValues=[org.apache.shardingsphere.core.parse.old.parser.expression.SQLPlaceholderExpression@d611f1c, org.apache.shardingsphere.core.parse.old.parser.expression.SQLPlaceholderExpression@4f2d014a, org.apache.shardingsphere.core.parse.old.parser.expression.SQLPlaceholderExpression@51fc862e])])
2022-06-13 13:47:59.977 INFO 7384 --- [ main] ShardingSphere-SQL : Actual SQL: db1 ::: INSERT INTO order_2 (user_id, product_name, COUNT, order_id) VALUES (?, ?, ?, ?) ::: [108, 大冰箱8, 10, 743103497402056705]
2022-06-13 13:48:00.036 INFO 7384 --- [ main] ShardingSphere-SQL : Rule Type: sharding
2022-06-13 13:48:00.036 INFO 7384 --- [ main] ShardingSphere-SQL : Logic SQL: INSERT INTO order(user_id,product_name,COUNT) VALUES(?,?,?)
2022-06-13 13:48:00.036 INFO 7384 --- [ main] ShardingSphere-SQL : SQLStatement: InsertStatement(super=DMLStatement(super=AbstractSQLStatement(type=DML, tables=Tables(tables=[Table(name=order, alias=Optional.absent())]), routeConditions=Conditions(orCondition=OrCondition(andConditions=[AndCondition(conditions=[])])), encryptConditions=Conditions(orCondition=OrCondition(andConditions=[])), sqlTokens=[TableToken(tableName=order, quoteCharacter=NONE, schemaNameLength=0), SQLToken(startIndex=17)], parametersIndex=3, logicSQL=INSERT INTO order(user_id,product_name,COUNT) VALUES(?,?,?)), deleteStatement=false, updateTableAlias={}, updateColumnValues={}, whereStartIndex=0, whereStopIndex=0, whereParameterStartIndex=0, whereParameterEndIndex=0), columnNames=[user_id, product_name, COUNT], values=[InsertValue(columnValues=[org.apache.shardingsphere.core.parse.old.parser.expression.SQLPlaceholderExpression@d611f1c, org.apache.shardingsphere.core.parse.old.parser.expression.SQLPlaceholderExpression@4f2d014a, org.apache.shardingsphere.core.parse.old.parser.expression.SQLPlaceholderExpression@51fc862e])])
2022-06-13 13:48:00.036 INFO 7384 --- [ main] ShardingSphere-SQL : Actual SQL: db1 ::: INSERT INTO order_1 (user_id, product_name, COUNT, order_id) VALUES (?, ?, ?, ?) ::: [109, 大冰箱9, 10, 743103497649520640]
我们再看看数据库:
order2:
order1:
非常完美,直接成功,接下来就是直接执行查询,然后去查询我们对应表中的数据。
我们再来一个测试看一下:
@Test
public void testFindOrderByIds(){
List<Long> ids = new ArrayList<>();
ids.add(743103495833387008L);
ids.add(743103495321681921L);
List<Map> list = orderDao.findOrderByIds(ids);
System.out.println(list);
}
同样的,我们给定1表和2表中的一个order_id 来进行 In 查询,看是否能正确返回我们想要的数据:
/**
* 根据ID 查询订单
* */
@Select({"<script>"+
"select * from order p where p.order_id in " +
"<foreach collection='orderIds' item='id' open='(' separator = ',' close=')'>#{id}</foreach>"
+"</script>"})
List<Map> findOrderByIds(@Param("orderIds") List<Long> orderIds);
接下来就是看结果的时刻,
[{user_id=101, COUNT=10, order_id=743103495833387008, product_name=大冰箱1}, {user_id=100, COUNT=10, order_id=743103495321681921, product_name=大冰箱0}]
很成功,我们使用Sharding-JDBC 进行单库水平切分表的操作已经完成了。你学会了么?