Backup tables for oracle

create or replace procedure sp_backuptable(v_nowtablename    varchar2, --product table name
                                           v_baktablename    varchar2, --backup table name,like test not like zxdbp_vpbx.test
                                           v_nowkeepdaynum   int, --keep day number of product table records
                                           v_bakkeepdaynum   int, --keep day number of backup table records
   v_datefield       varchar2, --field culumn
                                           v_datefieldformat varchar2, --date format of field culumn
                                           v_dopernum        int, --time interval of bach commition,the unit is second
                                           v_extcond         varchar2 --extention condition for query field
                                           ) as
  v_nowkeeptodate   varchar2(300); --keep date of product table records
  v_bakkeeptodate   varchar2(300); --keep date of product table records
  v_strcheck        varchar2(2000);
  v_strsql          varchar2(8000);
  v_tmpbegindate    varchar2(500);
  v_tmpnowbegindate varchar2(300);
  v_tmpnowenddate   varchar2(300);
  v_tmpbakbegindate varchar2(300);
  v_tmpbakenddate   varchar2(300);

  v_exsistpbase     varchar2(300);
  v_exsistpnew      varchar2(300);
  v_p               varchar2(300);
  v_seq             number;

  v_change_dopernum        int;
  v_change_datefieldformat varchar2(300);
  v_count                  int;
  v_datefieldischar        int; --if the date format is character format

cursor cur_plist is
   select PARTITION_NAME
   from user_tab_partitions
   where table_name = upper(v_baktablename) and PARTITION_NAME< 'P'||to_char(trunc(sysdate-v_bakkeepdaynum,'month'),'yyyymm') and PARTITION_NAME != 'PBASE';

begin
  select backup_seq.nextval into v_seq from dual;
  insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'sp_backuptable('
  ||''''||v_nowtablename||''','
  ||''''||v_baktablename||''','
  ||v_nowkeepdaynum||','
  ||v_bakkeepdaynum||','
  ||''''||v_datefield||''','
  ||''''||v_datefieldformat||''','
  ||v_dopernum||','
  ||''''||v_extcond||''''
  ||').');
  commit;
  --begin to check parameters
  insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Check parameters.');
  commit;
  v_change_dopernum := v_dopernum;
  if (v_datefieldformat not in
     ('datetime', 'yyyy.mm.dd', 'yyyy-mm-dd', 'yyyy/mm/dd', 'yyyymmdd',
      'yyyy.mm.dd hh', 'yyyy-mm-dd hh', 'yyyy/mm/dd hh', 'yyyymmddhh',
      'yyyy.mm.dd hh:mi:ss', 'yyyy-mm-dd hh:mi:ss', 'yyyy/mm/dd hh:mi:ss',
      'yyyymmddhhmiss')) then
    insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Error:date format is wrong.');
  commit;
  return;
  end if;

   select count(1)
    into v_count
    from user_tables
   where table_name = upper(v_nowtablename)
     and rownum < 2;
  if v_count <= 0 then
    insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Error:product table does not exists.');
    commit;
    return;
  end if;

  select count(1)
    into v_count
    from user_tables
   where table_name = upper(v_baktablename)
     and rownum < 2;
  if v_count <= 0 then
    insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Error:backup table does not exists.');
    commit;
    return;
  end if;

  select count(1)
    into v_count
    from user_tab_columns
   where table_name = upper(v_nowtablename)
     and column_name = upper(v_datefield)
     and rownum < 2;
  if v_count <= 0 then
    insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Error:column does not exists.');
    commit;
    return;
  end if;

  if v_nowkeepdaynum < 0 then
    insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Error:keep day number of product table is less than zero.');
    commit;
    return;
  end if;
  if v_bakkeepdaynum < 0 then
    insert into backup_log(operation,prodtablename,msg) values(v_seq,v_bakkeepdaynum,'Error:keep day number of backup table is less than zero.');
    commit;
    return;
  end if;
  if v_change_dopernum <= 0 then
    insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Error:commit time interval is less than zero.');
    commit;
    return;
  end if;

  select replace(v_datefieldformat, 'hh', 'hh24')
    into v_change_datefieldformat
    from dual;
  v_datefieldischar := 1;
  if (v_datefieldformat = 'datetime') then
    v_tmpbegindate    := 'nvl(min(' || v_datefield || '),sysdate)';
    v_tmpnowbegindate := 'v_nowbegindate';
    v_tmpnowenddate   := 'v_nowenddate';
    v_tmpbakbegindate := 'v_bakbegindate';
    v_tmpbakenddate   := 'v_bakenddate';
    v_datefieldischar := 0;
  else
    if (v_datefieldformat in
       ('yyyy.mm.dd', 'yyyy/mm/dd', 'yyyy-mm-dd', 'yyyymmdd')) then
      v_change_dopernum := 1440;
    elsif (v_datefieldformat in
          ('yyyy.mm.dd hh', 'yyyy/mm/dd hh', 'yyyy-mm-dd hh', 'yyyymmddhh')) then
      v_change_dopernum := 60;
    end if;

    v_tmpbegindate    := 'to_date(nvl(min(' || v_datefield ||
                         '),to_char(sysdate,''' || v_change_datefieldformat ||
                         ''')),''' || v_change_datefieldformat || ''')';
    v_tmpnowbegindate := 'to_char(v_nowbegindate,''' ||
                         v_change_datefieldformat || ''')';
    v_tmpnowenddate   := 'to_char(v_nowenddate,''' ||
                         v_change_datefieldformat || ''')';
    v_tmpbakbegindate := 'to_char(v_bakbegindate,''' ||
                         v_change_datefieldformat || ''')';
    v_tmpbakenddate   := 'to_char(v_bakenddate,''' ||
                         v_change_datefieldformat || ''')';

  end if;

  --keep date
  v_nowkeeptodate := 'trunc(sysdate)-' || v_nowkeepdaynum;
  v_bakkeeptodate := 'trunc(sysdate)-' || v_bakkeepdaynum;

  --check format sql
  v_strcheck := '';
  if v_datefieldischar = 0 then
    v_strcheck := '
v_count :=0;
select count(1) into v_count from ' || v_nowtablename ||
                  ' where rownum<2;
if v_count = 0 then
select count(1) into v_count from ' ||
                  v_baktablename || ' where rownum<2;
if v_count = 0 then
       return;
else
select ' || v_datefield ||
                  ' into v_checkdate from ' || v_baktablename ||
                  ' where rownum<2;
end if;
else
select ' || v_datefield ||
                  ' into v_checkdate from ' || v_nowtablename || ' where rownum<2;
end if;

  if v_checkdate is null then
return;
end if;
if v_checkdate <> to_date(to_char(v_checkdate,
''yyyymmddhh24miss''),
''yyyymmddhh24miss'') then
insert into backup_log(operation,prodtablename,msg) values('||v_seq||','''||v_nowtablename||''',''Error:date format is wrong.'');
  commit;
  return;
end if;';
  else
    v_strcheck := '
v_count :=0;
select count(1) into v_count from ' || v_nowtablename ||
                  ' where rownum<2;
if v_count = 0 then
select count(1) into v_count from ' || v_baktablename ||
                  ' where rownum<2;
if v_count = 0 then
return;
else
select ' || v_datefield ||
                  ' into v_strcheckdate from ' || v_baktablename ||
                  ' where rownum<2;
end if;
else
select ' || v_datefield || ' into v_strcheckdate from ' ||
                  v_nowtablename || ' where rownum<2;
end if;

if v_strcheckdate is null then
return;
end if;
if v_strcheckdate <> to_char(to_date(v_strcheckdate,
''' || v_change_datefieldformat || '''),
''' || v_change_datefieldformat || ''') then
insert into backup_log(operation,prodtablename,msg) values('||v_seq||','''||v_nowtablename||''',''Error:date format is wrong.'');
  commit;
  return;
end if;';
  end if;

  --begin add new partitions.
  insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Add new partitions.');
  commit;
  select count(*) into v_exsistpbase from user_tab_partitions where table_name = upper(v_baktablename) and partition_name = 'PBASE';
  select count(*) into v_exsistpnew from user_tab_partitions where table_name = upper(v_baktablename) and partition_name = 'P'|| to_char(add_months(trunc(sysdate-v_nowkeepdaynum,'month'),1),'yyyymm');
  if ( v_exsistpbase = 1 and v_exsistpnew = 0 ) then
  begin
  insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Add partition p'||lower(to_char(add_months(trunc(sysdate-v_nowkeepdaynum,'month'),1),'yyyymm'))||'.');
  commit;
  if (v_datefieldformat = 'datetime') then
  v_strsql := ' alter table '||v_baktablename||' split partition pbase at (to_date('''
               || to_char(add_months(add_months(trunc(sysdate-v_nowkeepdaynum,'month'),1),1),'yyyymm')||''',''yyyymm''))'
               ||' INTO'
               ||' (partition P' || to_char(add_months(trunc(sysdate-v_nowkeepdaynum,'month'),1),'yyyymm')
               ||' ,partition PBASE)';
  else
    v_strsql := ' alter table '||v_baktablename||' split partition pbase at ('''
               ||to_char(add_months(add_months(trunc(sysdate-v_nowkeepdaynum,'month'),1),1),v_change_datefieldformat)||''')'
               ||' INTO'
               ||' (partition P' || to_char(add_months(trunc(sysdate-v_nowkeepdaynum,'month'),1),'yyyymm')
               ||' ,partition PBASE)';
  end if;
      begin
  execute immediate v_strsql;
  exception when others then
  begin
  insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Error:execute dynamic sql '||substr(v_strsql,1,3900));
  commit;
  return;
  end;
  end;
  end;
  end if;
  --end of add new partitions.

  --begin to move data from product table to backup table.
  insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Move data,keep data in table '
  ||v_nowtablename||' from time '||to_char(sysdate-v_nowkeepdaynum,'yyyymmddhh24miss')||' to now'
  ||',keep data in table '
  ||v_baktablename||' from time '||to_char(trunc(sysdate-v_bakkeepdaynum,'month'),'yyyymmddhh24miss')||' to '||to_char(sysdate-v_nowkeepdaynum,'yyyymmddhh24miss')||'.');
  commit;
  v_strsql := 'declare
v_nowbegindate  date;
v_nowenddate    date;
v_bakbegindate  date;
v_bakenddate    date;
v_rows int;
v_checkdate     date;
v_strcheckdate  varchar2(100);
v_count int;
begin
' || v_strcheck || '
select ' || v_tmpbegindate || ' into v_nowbegindate from ' ||
              v_nowtablename || ' where 1=1 ' || v_extcond || ';
v_nowenddate := v_nowbegindate+' || v_change_dopernum ||
              '/1440;
if v_nowenddate>' || v_nowkeeptodate || ' then
v_nowenddate:=' || v_nowkeeptodate || ';
end if;
v_bakenddate:=' || v_bakkeeptodate || ';
while (v_nowbegindate < ' || v_nowkeeptodate ||
              ') loop
insert into ' || v_baktablename || ' select * from ' ||
              v_nowtablename || '
where ' || v_datefield || '>=' || v_tmpnowbegindate || '
and ' || v_datefield || '<=' || v_tmpnowenddate || ' ' ||
              v_extcond || ';
delete from ' || v_nowtablename || ' where ' || v_datefield || '>=' ||
              v_tmpnowbegindate || '
and ' || v_datefield || '<=' || v_tmpnowenddate || ' ' ||
              v_extcond || ';
commit;
select ' || v_tmpbegindate || '
into v_nowbegindate from
' || v_nowtablename || ' where 1=1
' || v_extcond || ';
v_nowenddate := v_nowbegindate+' || v_change_dopernum ||
              '/1440;
if v_nowenddate>' || v_nowkeeptodate || ' then
v_nowenddate:=' || v_nowkeeptodate || ';
end if;
end loop;
end;';

begin
  execute immediate v_strsql;
exception when others then
  begin
  insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Error:execute dynamic sql '||substr(v_strsql,1,3900));
  commit;
  return;
  end;
  end;
  --end of move data from product table to backup table.

--begin to drop the old partitions.
insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Drop the old partitions.');
commit;
open cur_plist;
loop
fetch cur_plist into v_p;
exit when cur_plist%notfound;
  begin
  insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Drop partition '||lower(v_p)||'.');
  commit;
begin
execute immediate 'alter table '||v_baktablename||' drop partition ' || v_p; -- drop the partition.
  exception when others then
  begin
  insert into backup_log(operation,prodtablename,msg) values(v_seq,v_nowtablename,'Error:execute dynamic sql '||substr(v_strsql,1,3900));
  commit;
  return;
  end;
  end;
end;
end loop;
close cur_plist;
--end of drop the old partitions.
end;
/