修改表结构的语句

修改表结构，同时保存数据。

create table ks_back as select * from xml.ldp_qry_details_daily where 1=2;insert into ks_back select * from ldp_qry_details_back;commit;delete from ldp_qry_details_back;commit;alter table LDP_QRY_DETAILS_BACK modify MSISDN number(30);alter table LDP_QRY_DETAILS_BACK modify BRAND_NAME varchar2(30);alter table LDP_QRY_DETAILS_BACK modify DEAL_NAME varchar2(300);alter table LDP_QRY_DETAILS_BACK modify STATUS_GROUP varchar2(30);alter table LDP_QRY_DETAILS_BACK modify CREATE_TIME number(30);alter table LDP_QRY_DETAILS_BACK modify SALE_ID number(30);alter table LDP_QRY_DETAILS_BACK modify CREATE_DATE number(30);alter table LDP_QRY_DETAILS_BACK modify INURE_DATE number(30);alter table LDP_QRY_DETAILS_BACK modify SUM_DATE number(30);insert into ldp_qry_details_back select * from ks_back;commit;drop table ks_back;commit;