[Solved] dynamic-datasource can not find primary datasource

Error reporting details

When using mybatis plus multiple data sources, the startup message cannot find the master data source

com.baomidou.dynamic.datasource.exception.CannotFindDataSourceException: dynamic-datasource can not find primary datasource
	at com.baomidou.dynamic.datasource.DynamicRoutingDataSource.determinePrimaryDataSource(DynamicRoutingDataSource.java:91) ~[dynamic-datasource-spring-boot-starter-3.5.1.jar:3.5.1]
	at com.baomidou.dynamic.datasource.DynamicRoutingDataSource.getDataSource(DynamicRoutingDataSource.java:120) ~[dynamic-datasource-spring-boot-starter-3.5.1.jar:3.5.1]
	at com.baomidou.dynamic.datasource.DynamicRoutingDataSource.determineDataSource(DynamicRoutingDataSource.java:78) ~[dynamic-datasource-spring-boot-starter-3.5.1.jar:3.5.1]
	at com.baomidou.dynamic.datasource.ds.AbstractRoutingDataSource.getConnection(AbstractRoutingDataSource.java:48) ~[dynamic-datasource-spring-boot-starter-3.5.1.jar:3.5.1]
......

Solution:

① The dependency of multiple data sources is introduced, but multiple data sources are not used

<!--This is the dependent version I use-->
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>dynamic-datasource-spring-boot-starter</artifactId>
    <version>3.5.1</version>
</dependency>

<!--document-->
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>dynamic-datasource-spring-boot-starter</artifactId>
    <version>${version}</version>
</dependency>

Multi data source usage: use @ds to switch data sources.

@DS can be annotated on methods or classes, and there is a proximity principle that annotations on methods take precedence over annotations on classes.

annotation result
no @DS Default data source
@DS(“databaseName”) databaseName can be a group name or the name of a specific library

② Multiple data sources are used but the main data source is not specified

spring:
  datasource:
    dynamic:
      primary: master # Set the default data source or data source group, the default value is master
      strict: false #Strictly match the datasource, default false. true does not match the specified datasource throw an exception, false uses the default datasource
      datasource:
        master:
          url: jdbc:mysql://xx.xx.xx.xx:3306/dynamic
          username: root
          password: 123456
          driver-class-name: com.mysql.jdbc.Driver # This configuration can be omitted for SPI support since 3.2.0
        slave_1:
          url: jdbc:mysql://xx.xx.xx.xx:3307/dynamic
          username: root
          password: 123456
          driver-class-name: com.mysql.jdbc.
        slave_2:
          url: ENC(xxxxxx) # Built-in encryption, please check the detailed documentation for use
          username: ENC(xxxxxxxxxx)
          password: ENC(xxxxxxxxxx)
          driver-class-name: com.mysql.jdbc.
       #...... omit
       #The above will configure a default library master, a group slave with two sub-banks slave_1,slave_2

③ Check carefully if there is any alignment in the configuration

# Correct format
spring:
  datasource:
    dynamic:
      strict: false
      primary: one
      datasource:
        one:
          driver-class-name: com.mysql.cj.jdbc.Driver
          url: jdbc:mysql://localhost:3306/demo?allowMultiQueries=true&zeroDateTimeBehavior=convertToNull&useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai&useSSL=false
          username: root
          password: 123456
        two:
          driver-class-name: com.mysql.cj.jdbc.Driver
          url: jdbc:mysql://localhost:3306/demo1?allowMultiQueries=true&zeroDateTimeBehavior=convertToNull&useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai&useSSL=false
          username: root
          password: 123456

 

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