org.postgresql.util.PSQLException: 错误: 关系 "act_ge_property" 不存在
先说解决方式：
删除act_*相关的表，然后手动重建表。act_ge_property表中有4行数据也要手动插入。
插入sql语句在activiti-engine-6.0.0.jar中有。
activiti-engine-6.0.0.jar!\org\activiti\db\create\activiti.postgres.create.engine.sql
activiti.postgres.create.history.sql
activiti.postgres.create.identity.sql
三个文件都要执行。
现象：
今天在使用databaseSchemaUpdate=drop-create属性配置启动项目后，
报出:
192.168.137.209 2019-06-25 15:40:14,371 ERROR (CommandContext.java:122)- Error while closing command context
org.apache.ibatis.exceptions.PersistenceException:
### Error querying database. Cause: org.postgresql.util.PSQLException: 错误: 关系 "act_ge_property" 不存在
位置：15
### The error may exist in org/activiti/db/mapping/entity/Property.xml
### The error may involve org.activiti.engine.impl.persistence.entity.PropertyEntityImpl.selectProperty-Inline
### The error occurred while setting parameters
### SQL: select * from ACT_GE_PROPERTY where NAME_ = ?
### Cause: org.postgresql.util.PSQLException: 错误: 关系 "act_ge_property" 不存在
位置：15
at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:150)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:77)
at org.activiti.engine.impl.db.DbSqlSession.selectById(DbSqlSession.java:364)
at org.activiti.engine.impl.db.DbSqlSession.selectById(DbSqlSession.java:348)
at org.activiti.engine.impl.db.DbSqlSession.dbSchemaUpdate(DbSqlSession.java:910)
at org.activiti.engine.impl.db.DbSqlSession.performSchemaOperationsProcessEngineBuild(DbSqlSession.java:1318)
at org.activiti.engine.impl.SchemaOperationsProcessEngineBuild.execute(SchemaOperationsProcessEngineBuild.java:28)
at org.activiti.engine.impl.interceptor.CommandInvoker$1.run(CommandInvoker.java:37)
at org.activiti.engine.impl.interceptor.CommandInvoker.executeOperation(CommandInvoker.java:78)
at org.activiti.engine.impl.interceptor.CommandInvoker.executeOperations(CommandInvoker.java:57)
at org.activiti.engine.impl.interceptor.CommandInvoker.execute(CommandInvoker.java:42)
at org.activiti.engine.impl.interceptor.TransactionContextInterceptor.execute(TransactionContextInterceptor.java:48)
at org.activiti.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:63)
at com.arvato.service.bpm.config.MyTransactionInterceptor.execute(MyTransactionInterceptor.java:48)
at org.activiti.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:29)
at org.activiti.engine.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:44)
at org.activiti.engine.impl.ProcessEngineImpl.
at org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl.buildProcessEngine(ProcessEngineConfigurationImpl.java:665)
at org.activiti.spring.SpringProcessEngineConfiguration.buildProcessEngine(SpringProcessEngineConfiguration.java:65)
at org.activiti.spring.ProcessEngineFactoryBean.getObject(ProcessEngineFactoryBean.java:57)
at org.activiti.spring.ProcessEngineFactoryBean.getObject(ProcessEngineFactoryBean.java:32)
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:171)
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getObjectFromFactoryBean(FactoryBeanRegistrySupport.java:101)
at org.springframework.beans.factory.support.AbstractBeanFactory.getObjectForBeanInstance(AbstractBeanFactory.java:1645)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getObjectForBeanInstance(AbstractAutowireCapableBeanFactory.java:1182)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:327)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:251)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1065)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:584)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:91)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:373)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1348)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:578)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:501)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:760)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550)
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:327)
at org.springframework.boot.builder.SpringApplicationBuilder.run(SpringApplicationBuilder.java:137)
at com.arvato.service.bpm.BpmServiceApplication.main(BpmServiceApplication.java:28)
Caused by: org.postgresql.util.PSQLException: 错误: 关系 "act_ge_property" 不存在
位置：15
at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2477)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:2190)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:300)
at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:428)
at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:354)
at org.postgresql.jdbc.PgPreparedStatement.executeWithFlags(PgPreparedStatement.java:169)
at org.postgresql.jdbc.PgPreparedStatement.execute(PgPreparedStatement.java:158)
at com.alibaba.druid.pool.DruidPooledPreparedStatement.execute(DruidPooledPreparedStatement.java:498)
at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:63)
at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79)
at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63)
at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:324)
at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109)
at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148)
... 49 common frames omitted