IT工程師數位筆記本

方法一：
首先建立一個計算函數
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
create or replace function count_rows(table_name in varchar2,
                              owner in varchar2 default null)
return number
authid current_user
IS
   num_rows number;
   stmt varchar2(2000);
begin
   if owner is null then
      stmt := 'select count(*) from "'||table_name||'"';
   else
      stmt := 'select count(*) from "'||owner||'"."'||table_name||'"';
   end if;
   execute immediate stmt into num_rows;
   return num_rows;
end;
然后通過計算函數進行統計
select table_name, count_rows(table_name) nrows from user_tables
獲取要統計的值
方法二：
select t.table_name,t.num_rows from user_tables t
查看記錄數，但是num_rows存儲的是上次分析后的值，不準確，要使用該方法，必須分析后才可以試用
完成的語句為

declare
v_tName varchar(50);
v_sqlanalyze varchar(500);
v_num number;
v_sql varchar(500);
cursor c1 
is
select table_name from user_tables;
begin
open c1;
loop
fetch c1 into v_tName;
if c1%found then

v_sqlanalyze :='analyze table  '||v_tName||'  estimate statistics';
execute immediate v_sqlanalyze;
v_sql := 'select NUM_ROWS  from user_tables where table_name =upper('''||v_tName||''')';

execute immediate v_sql into  v_num;
dbms_output.put_line('表名： '||v_tName||' 行數： '||v_num);
else
exit;
end if;
end loop;
end;