utl_raw.cast_to_raw
Oracle字符集查询
NLS_CHARACTERSET是数据库字符集，NLS_NCHAR_CHARACTERSET是国家字符集
ORACLE中有两大类字符型数据，VARCHAR2是按照数据库字符集来存储数据。而NVARCHAR2是按照国家字符集存储数据的。同样，CHAR和NCHAR也一样，一是数据库字符符，一是国家字符集。
字符集不同，二进制码的组合就不同
需求要求varchar2 加工插入blob
采用 utl_raw.cast_to_raw（‘你好啊’）,
mybatis 读取byte[] 转string
package com.hcp.util; import org.apache.ibatis.type.BaseTypeHandler; import org.apache.ibatis.type.JdbcType; import java.io.UnsupportedEncodingException; import java.nio.charset.Charset; import java.sql.*; public class BlobToStringTypeHandler extends BaseTypeHandler<String> { private static final String DEFAULT_CHARSET = "gbk"; // 这里和数据库编码一直，否则乱码、 实体保存的时候也要 getBytes("gbk") @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 { Blob blob = rs.getBlob(columnName); return handle(blob); } @Override public String getNullableResult(ResultSet rs, int columnIndex) throws SQLException { Blob blob = rs.getBlob(columnIndex); return handle(blob); } @Override public String getNullableResult(CallableStatement cs, int columnIndex) throws SQLException { Blob blob = cs.getBlob(columnIndex); return handle(blob); } private String handle( Blob blob)throws SQLException{ try { return blob == null?null:new String(blob.getBytes(1, (int)blob.length()),DEFAULT_CHARSET); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } return null; } }
<resultMap id="ResultMapWithHcpPjyjCx" type="HcpPjyjCx"> <id column="PJYJXH" jdbcType="VARCHAR" property="pjyjxh" /> <result column="PJJGXH" jdbcType="VARCHAR" property="pjjgxh" /> <result column="PJLY_DM" jdbcType="VARCHAR" property="pjlyDm" /> <result column="PJLYMC" jdbcType="VARCHAR" property="pjlyMc" /> <result column="YJJY" jdbcType="BLOB" property="yjjy" /> <result property="yjjynr" column="YJJYNR" jdbcType="BLOB" typeHandler="com.hcp.util.BlobToStringTypeHandler"></result> </resultMap>
