1、查看当前所有对象
SQL> select * from tab;
2、建一个和a表结构一样的空表
SQL> create table b as select * from a where 1=2;
SQL> create table b(b1,b2,b3) as select a1,a2,a3 from a where 1=2;
3、察看数据库的大小,和空间使用情况
SQL> col tablespace format a20
SQL>
select b.file_id 文件ID,
b.tablespace_name 表空间,
b.file_name 物理文件名,
b.bytes 总字节数,
(b.bytes-sum(nvl(a.bytes,0))) 已使用,
sum(nvl(a.bytes,0)) 剩余,
sum(nvl(a.bytes,0))/(b.bytes)*100 剩余百分比
from dba_free_space a,dba_data_files b
where a.file_id=b.file_id
group by b.tablespace_name,b.file_name,b.file_id,b.bytes
order by b.tablespace_name
/
dba_free_space --表空间剩余空间状况
dba_data_files --数据文件空间占用情况
4、查看现有回滚段及其状态
SQL> col segment format a30
SQL>
SELECT SEGMENT_NAME,OWNER,TABLESPACE_NAME,SEGMENT_ID,FILE_ID,STATUS FROM DBA_ROLLBACK_SEGS;
5、查看数据文件放置的路径
SQL> col file_name format a50
SQL>
select tablespace_name,file_id,bytes/1024/1024,file_name from dba_data_files order by file_id;
6、显示当前连接用户
SQL>
show user
7、把SQL*Plus当计算器
SQL> select 100*20 from dual;
8、连接字符串
SQL> select 列1||列2 from 表1;
SQL> select concat(列1,列2) from 表1;
9、查询当前日期
SQL> select to_char(sysdate,'yyyy-mm-dd,hh24:mi:ss') from dual;
10、用户间复制数据
SQL> copy from user1 to user2 create table2 using select * from table1;
11、视图中不能使用order by,但可用group by代替来达到排序目的
SQL> create view a as select b1,b2 from b group by b1,b2;
12、通过授权的方式来创建用户
SQL> grant connect,resource to test identified by test;
SQL> conn test/test
13、
相当有用的一个存储过程
--禁止或启用所有约束和触发器
CREATE OR REPLACE PROCEDURE P_ALTERCONS(
AS_ALTER VARCHAR2)
AS
v_CursorID INTEGER;
v_StrCon VARCHAR2(300);
v_StrTri VARCHAR2(300);
v_FkNum NUMBER :=0;
v_TriNum NUMBER :=0;
v_sqlcode NUMBER;
v_sqlerrm VARCHAR2(600);
CURSOR C_CON IS
SELECT * FROM USER_CONSTRAINTS
WHERE CONSTRAINT_TYPE='R';
R_CON C_CON%ROWTYPE;
CURSOR c_trigger IS
SELECT TRIGGER_NAME,STATUS FROM user_triggers;
notfound BOOLEAN;
BEGIN
DBMS_OUTPUT.PUT_LINE('BEGIN TIME: '||to_char(sysdate));
-- 判断输入参数是否为DISABLE或者是ENABLE,如果是的话,就继续处理,否则退出过程,给出提示
IF (UPPER(AS_ALTER) = 'DISABLE' OR UPPER(AS_ALTER) = 'ENABLE') THEN
OPEN C_CON;
-- 当前用户下外键的处理 ENABLE或者 DISABLE
v_CursorID := DBMS_SQL.OPEN_CURSOR;
LOOP
FETCH C_CON into R_CON;
notfound:=C_CON%NOTFOUND;
EXIT WHEN notfound;
begin
IF (UPPER(AS_ALTER)='DISABLE' AND R_CON.STATUS='ENABLED' OR
UPPER(AS_ALTER)='ENABLE' AND R_CON.STATUS='DISABLED') THEN
v_StrCon := 'ALTER TABLE '||R_CON.owner||'.'||R_CON.table_name||' '||
UPPER(as_alter) || ' CONSTRAINT '||R_CON.constraint_name;
DBMS_SQL.PARSE( v_CursorID, v_StrCon, DBMS_SQL.V7);
v_FkNum :=v_FkNum+1;
END IF;
EXCEPTION
WHEN OTHERS THEN
v_sqlcode := SQLCODE;
v_sqlerrm := SUBSTR(SQLERRM,1,600);
DBMS_OUTPUT.PUT_LINE('ERROR: '||' '||V_SQLERRM);
-- 找出错误原因
IF (v_sqlcode = -2298) THEN
p_con_err(R_CON.CONSTRAINT_NAME);
END IF;
END;
END LOOP;
CLOSE C_CON;
DBMS_OUTPUT.PUT_LINE('====== Foreign Keys were '||as_alter||', total '||to_char(v_FkNum)||' =====');
-- 当前用户下触发器的处理 ENABLE或者 DISABLE
FOR T_TRIGGER IN C_TRIGGER LOOP
BEGIN
IF (UPPER(AS_ALTER)='DISABLE' AND T_TRIGGER.STATUS='ENABLED' OR
UPPER(AS_ALTER)='ENABLE' AND T_TRIGGER.STATUS='DISABLED') THEN
v_StrTri := 'ALTER TRIGGER '||T_TRIGGER.TRIGGER_name ||' '||UPPER(as_alter);
DBMS_SQL.PARSE( v_CursorID, v_StrTri, DBMS_SQL.V7);
v_TriNum :=v_TriNum+1;
END IF;
EXCEPTION
WHEN OTHERS THEN
v_sqlcode := SQLCODE;
v_sqlerrm := SUBSTR(SQLERRM,1,600);
DBMS_OUTPUT.PUT_LINE('ERROR: '||V_SQLCODE||' '||V_SQLERRM);
END;
END LOOP;
DBMS_OUTPUT.PUT_LINE('====== Triggers were '||as_alter||', total '||to_char(v_TriNum)||' =====');
DBMS_SQL.CLOSE_CURSOR(v_CursorID);
ELSE -- 输入参数不正确
DBMS_OUTPUT.PUT_LINE('ERROR:输入参数不正确,参数为ENABLE或者DISABLE!');
END IF;
DBMS_OUTPUT.PUT_LINE('END TIME: '||to_char(sysdate));
END;
/
--显示oracle的错误
CREATE OR REPLACE PROCEDURE P_CON_ERR(as_constraint_name varchar2)
AS
v_CursorID INTEGER;
V_CONSNAME VARCHAR2(30);
V_TABLE_NAME VARCHAR2(30);
V_RTABLE_NAME VARCHAR2(30);
V_COLUMN VARCHAR2(100);
v_Str VARCHAR2(600);
TYPE t_col_value IS TABLE OF VARCHAR2(30)
INDEX BY BINARY_INTEGER;
v_Col_Val t_col_value;
v_RET NUMBER;
v_NUM NUMBER;
i BINARY_INTEGER;
V_WHERE VARCHAR2(600);
V_CAUSE VARCHAR2(200);
CURSOR C_COL_NAME(V_CON_NAME VARCHAR2) IS
SELECT * FROM USER_CONS_COLUMNS
WHERE CONSTRAINT_NAME=V_CON_NAME;
BEGIN
V_CONSNAME := TRIM(UPPER(as_constraint_name)); -- 约束名称
v_num :=0;
FOR T_COL_NAME IN C_COL_NAME(V_CONSNAME) LOOP
IF (V_NUM = 0) THEN
V_COLUMN :=T_COL_NAME.COLUMN_NAME;
V_WHERE :='A.'||T_COL_NAME.COLUMN_NAME||'= B.'||T_COL_NAME.COLUMN_NAME;
ELSE
V_COLUMN :=V_COLUMN||','||T_COL_NAME.COLUMN_NAME;
V_WHERE :=V_WHERE||' AND '||'A.'||T_COL_NAME.COLUMN_NAME||'= B.'||T_COL_NAME.COLUMN_NAME;
END IF;
V_NUM :=V_NUM+1;
END LOOP;
FOR I IN 1..V_NUM LOOP
V_COL_VAL(I) :='';
END LOOP;
SELECT DISTINCT TABLE_NAME INTO V_TABLE_NAME FROM USER_CONS_COLUMNS
WHERE CONSTRAINT_NAME = V_CONSNAME;
-- 找到被引用的表名称
SELECT TABLE_NAME INTO V_RTABLE_NAME FROM USER_CONSTRAINTS
WHERE CONSTRAINT_NAME IN (SELECT R_CONSTRAINT_NAME FROM USER_CONSTRAINTS
WHERE CONSTRAINT_NAME = V_CONSNAME);
DBMS_OUTPUT.PUT_LINE('外键错误情况');
DBMS_OUTPUT.PUT_LINE('============');
DBMS_OUTPUT.PUT_LINE(v_column);
DBMS_OUTPUT.PUT_LINE(RPAD('-',LENGTH(V_COLUMN),'-'));
v_CursorID := DBMS_SQL.OPEN_CURSOR;
V_STR := 'SELECT DISTINCT '||V_COLUMN||' FROM '||V_TABLE_NAME||' A WHERE NOT EXISTS ( SELECT NULL FROM '
||V_RTABLE_NAME||' B WHERE '||V_WHERE||')';
DBMS_SQL.PARSE( v_CursorID, v_Str, DBMS_SQL.V7);
FOR I IN 1..V_NUM LOOP
DBMS_SQL.DEFINE_COLUMN(v_CursorID,I,v_COL_VAL(I),30);
END LOOP;
v_ret := DBMS_SQL.EXECUTE(v_CursorID);
WHILE DBMS_SQL.FETCH_ROWS(v_CursorID) > 0 LOOP
V_CAUSE :='';
FOR I IN 1..V_NUM LOOP
DBMS_SQL.COLUMN_VALUE(v_CursorID,I,V_COL_VAL(I));
IF (I = 1) THEN
V_CAUSE :=V_COL_VAL(I);
ELSE
V_CAUSE :=V_CAUSE||', '||V_COL_VAL(I);
END IF;
END LOOP;
DBMS_OUTPUT.PUT_LINE(V_CAUSE);
END LOOP;
DBMS_SQL.CLOSE_CURSOR(v_CursorID);
END;
/
用法:
exec p_altercons(‘DISABLE');
exec p_altercons('ENABLE');