使用shardingsphere对SQLServer坑的解决

<!--sharding-->

< dependency >

     < groupId >org.apache.shardingsphere</ groupId >

     < artifactId >sharding-jdbc-spring-boot-starter</ artifactId >

     < version >4.0.1</ version >

</ dependency >

< dependency >

     < groupId >com.alibaba</ groupId >

     < artifactId >druid-spring-boot-starter</ artifactId >

     < version >1.2.8</ version >

</ dependency >

package cn.preserve.config.mybatis;

import org.apache.ibatis.type.BaseTypeHandler;

import org.apache.ibatis.type.JdbcType;

import org.apache.ibatis.type.MappedJdbcTypes;

import org.apache.ibatis.type.TypeException;

import java.sql.CallableStatement;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

/**

  *  将 nvarchar 转成 varchar  sharingJDBC不支持nvarchar

  *  主要是NStringTypeHandler中，没有setNString()

  */

@MappedJdbcTypes (JdbcType.NVARCHAR)

public class NVarcharTypeHandler extends BaseTypeHandler<String> {

     @Override

     public void setParameter(PreparedStatement ps, int i, String parameter, JdbcType jdbcType) throws SQLException {

         if (parameter == null ) {

             if (jdbcType == null ) {

                 throw new TypeException( "JDBC requires that the JdbcType must be specified for all nullable parameters." );

             }

             try {

                 ps.setNull(i, jdbcType.TYPE_CODE);

             } catch (SQLException var7) {

                 throw new TypeException( "Error setting null for parameter #" + i + " with JdbcType " + jdbcType + " . " + "Try setting a different JdbcType for this parameter or a different jdbcTypeForNull configuration property. " + "Cause: " + var7, var7);

             }

         } else {

             try {

                 this .setNonNullParameter(ps, i, parameter, jdbcType);

             } catch (Exception var6) {

                 throw new TypeException( "Error setting non null for parameter #" + i + " with JdbcType " + jdbcType + " . " + "Try setting a different JdbcType for this parameter or a different configuration property. " + "Cause: " + var6, var6);

             }

         }

     }

     /**

      * 这里使用setNString而不是setString

      * @param ps

      * @param i

      * @param parameter

      * @param jdbcType

      * @throws SQLException

      */

     @Override

     public void setNonNullParameter(PreparedStatement ps, int i, String parameter, JdbcType jdbcType) throws SQLException {

         ps.setString(i, parameter);

     }

     @Override

     public String getNullableResult(ResultSet rs, String columnName) throws SQLException {

         return rs.getString(columnName);

     }

     @Override

     public String getNullableResult(ResultSet rs, int columnIndex) throws SQLException {

         return rs.getString(columnIndex);

     }

     @Override

     public String getNullableResult(CallableStatement cs, int columnIndex) throws SQLException {

         return cs.getString(columnIndex);

     }

}

@Configuration

public class DataSourceConfig {

     @Bean (name = "sqlSessionFactory" )

     @Primary

     public SqlSessionFactory memberDb1SqlSessionFactory(DataSource dataSource)

             throws Exception {

         SqlSessionFactoryBean bean = getSqlSessionFactoryBean(dataSource);

         bean.setTypeHandlers( new TypeHandler[] { new NVarcharTypeHandler()});

         return bean.getObject();

     }

    // ******* 其他实现

}

< typeHandlers >

     < typeHandler handler = "cn.preserve.config.mybatis.NVarcharTypeHandler" />

</ typeHandlers >