1. 查询本节点及本节点以下的所有节点：
sql;">
select * from table1 c start with c.p_id='0000000' connect by prior c.id=c.p_id and c.use_yn='Y' order by id ;
2. 查询节点中所有的层级关系
CONNECT_BY_ROOT 返回当前节点的最顶端节点
2> CONNECT_BY_ISLEAF 判断是否为叶子节点，如果这个节点下面有子节点，则不为叶子节点
3> LEVEL 伪列表示节点深度
4> SYS_CONNECT_BY_PATH函数显示详细路径，并用“/”分隔
3. 对数据库表结构的操作
sql;">
alter table taxasset add (NEXTDATE varchar2(30));
alter table tax_dep_manager modify FDDBRXM varchar2(120);
alter table test1 drop column name;
4. 其他查询
sql;">
/*用户被占用的查询*/
select 'alter system kill session '''||sid||','||serial#||''';' from v$session where username = 'USERS';
/* 系统数据库相关查询 */
select * from user_tablespaces;
select username,default_tablespace from dba_users where username='ZZS'
select count(*) from user_views; --yb53 zzs 53
select count(*) from user_tables; --yb413 zzs 413
--查询表空间使用情况
SELECT Upper(F.TABLESPACE_NAME) "表空间名",D.TOT_GROOTTE_MB "表空间大小(M)",D.TOT_GROOTTE_MB - F.TOTAL_BYTES "已使用空间(M)",To_char(Round(( D.TOT_GROOTTE_MB - F.TOTAL_BYTES ) / D.TOT_GROOTTE_MB * 100,2),'990.99')|| '%' "使用比",F.TOTAL_BYTES "空闲空间(M)",F.MAX_BYTES "最大块(M)" FROM (SELECT TABLESPACE_NAME,Round(Sum(BYTES) / ( 1024 * 1024 ),2) TOTAL_BYTES,Round(Max(BYTES) / ( 1024 * 1024 ),2) MAX_BYTES FROM SYS.DBA_FREE_SPACE
GROUP BY TABLESPACE_NAME) F,(SELECT DD.TABLESPACE_NAME,Round(Sum(DD.BYTES) / ( 1024 * 1024 ),2) TOT_GROOTTE_MB
FROM SYS.DBA_DATA_FILES DD
GROUP BY DD.TABLESPACE_NAME) D
WHERE D.TABLESPACE_NAME = F.TABLESPACE_NAME
ORDER BY 1
--查询表空间的free space
select tablespace_name,count(*) AS extends,round(sum(bytes) / 1024 / 1024,2) AS MB,sum(blocks) AS blocks
from dba_free_space
group BY tablespace_name;
--查询表空间的总容量
select tablespace_name,sum(bytes) / 1024 / 1024 as MB from dba_data_files group by tablespace_name;
--表空间容量查询
SELECT TABLESPACE_NAME "表空间",To_char(Round(BYTES / 1024,'99990.00')
|| '' "实有",To_char(Round(FREE / 1024,'99990.00')
|| 'G' "现有",To_char(Round(( BYTES - FREE ) / 1024,'99990.00')
|| 'G' "使用",To_char(Round(10000 * USED / BYTES) / 100,'99990.00')
|| '%' "比例"
FROM (SELECT A.TABLESPACE_NAME TABLESPACE_NAME,Floor(A.BYTES / ( 1024 * 1024 )) BYTES,Floor(B.FREE / ( 1024 * 1024 )) FREE,Floor(( A.BYTES - B.FREE ) / ( 1024 * 1024 )) USED
FROM (SELECT TABLESPACE_NAME TABLESPACE_NAME,Sum(BYTES) BYTES
FROM DBA_DATA_FILES
GROUP BY TABLESPACE_NAME) A,(SELECT TABLESPACE_NAME TABLESPACE_NAME,Sum(BYTES) FREE
FROM DBA_FREE_SPACE
GROUP BY TABLESPACE_NAME) B
WHERE A.TABLESPACE_NAME = B.TABLESPACE_NAME)
ORDER BY Floor(10000 * USED / BYTES) DESC;
6. loop 的使用
100;
END LOOP;
DBMS_OUTPUT.PUT_LINE('完了');
END;
7. 存储过程的书写
sql;">
create or replace procedure InsertBranch(tablename in varchar2) as
counts number;
num number;
begin
create table tempdata (column1 nvarchar2,column2 nvarchar2,column3 nvarchar2);
insert tempdata
num := 1;
select count(*) into counts from tablename;
dbms_output.put_line('数据总数'+counts);
while num <= counts loop
dbms_output.put_line('循环开始:');
dbms_output.put_line('第'+num+'条数据');
select column1
into column1
from (select tablename.*,rownum as con from tablename)
where con = num;
select column2
into column2
from (select tablename.*,rownum as con from tablename)
where con = num;
select column3
into column3
from (select tablename.*,rownum as con from tablename)
where con = num;
insert into COM_DEPARTMENT
values
(brno,brname,upbrno,'N',null,'1','Y','2',2,brno,'A',3,'0',null);
num := num + 1;
end loop;
end;
原文链接：https://www.f2er.com/oracle/65049.html