$与#的区别
select * from T_PRINT_LAYOUT where D_RECID = ${recId}
最后生成的SQL为:
select * from T_PRINT_LAYOUT where D_RECID = 1
即:直接将参数值替换到了原来${recId}的位置,相当于硬拼SQL
select * from T_PRINT_LAYOUT where D_RECID = #{recid,jdbcType=DECIMAL}
最后生成的SQL为:
select * from T_PRINT_LAYOUT where D_RECID = ?
即:#{...}被识别为一个SQL参数