关于数据库如何分表

insert into bar_code_cmmdty_0 (bar_code,cmmdty_code,version)  select bar_code,cmmdty_code,version from cmmdty_bar_code where bar_code is not null and bar_code !='' and (bar_code REGEXP '[^0-9]')=0 and convert(bar_code,SIGNED) mod 8 = 0;

public CmmdtyBarCodeEntity queryCmmdtyBarCodeByBarCode(String barCode) {
int index = CommonUtils.getCmmdtyTableIndex(barCode);
Map<String, Object> paramMap = Maps.newHashMap();
paramMap.put("barCode", barCode);
paramMap.put("index", index);
return readDalClient.queryForObject(NAMESPACE.concat(CONTACT_MARK).concat(QUERY_CMMDTYBARCODE_BY_BAR_CODE), paramMap,
CmmdtyBarCodeEntity.class);
}

/**
*
* 功能描述: 获取商品条码表下标 <br>
* 〈功能详细描述〉获取商品条码表下标
*
* @param code
* @return
* @see [相关类/方法](可选)
* @since [产品/模块版本](可选)
*/
public static int getCmmdtyTableIndex(String code) {
if (isNumeric(code)) {
int mod = ScmConfUtil.getInstance().getInt("cmmdtyTableCount", CMMDTY_COUNT);
Long codeNum = Long.parseLong(code);
return (int) (codeNum % mod);
} else {
return MAX_INDEX;
}
}

<sql id="queryCmmdtyBarCodeByBarCode">
<![CDATA[
select
bar_code as barCode,
cmmdty_code as cmmdtyCode,
version as version
from bar_code_cmmdty_:index
where 1=1
and bar_code =:barCode
]]>
</sql>